Is the goal of mindfulness to develop ultimate dissociation? I came across this interpretation of Buddha's teaching that suggests that the Buddha ultimately sought a dissociative state, rather than one of freedom.

the buddhistic mindfulness meditation does not ... (a) stress genuine freedom, peace and happiness ... and (b) does not eliminate the genetically-encoded instinctual passions of fear, aggression, nurture and desire (the root cause of human bondage, malice and sorrow) ... and (c) does promise a mythical ‘freedom’ in an imaginary life-after-death (‘Parinirvana’) ... and (d) is not a new, non-spiritual method ... and (e) does not produce an actual freedom from the instinctual animal passions, here and now, on earth, in this lifetime ... and (f) does not offer a step by step, down-to-earth, practical progression to becoming actually free of the human condition of malice and sorrow ... to be both happy and harmless.
More to your point, however, Mr. Gotama the Sakyan’s mindfulness meditation is primarily about detachment/ dissociation from life – all existence is Dukkha due to Anicca (impermanence) and Dukkha comes from Tanha (craving) for Samsara (phenomenal existence) – and any meditation technique which stresses involvement with such is anything but what Mr. Gotama the Sakyan taught.

So my question is: is anyone that practices mindfulness, as advised by Buddhist teachers, heading towards developing a sort of dissociation from their feelings?
If not, how can anyone explain the fact of enlightened Buddhists still getting angry without referencing psychological dissociation?
Clarification 1
Some people expressed confusion over that question at the end. My clarification follows.
We can agree that Buddhist enlightenment does not guarantee extirpation of emotions (like anger). Thus, feeling angry (for example) does not invalidate someone's enlightenment. Enlightened beings can feel angry. Now, Richard says -- and this has been confirmed by the actually free people -- &quot;I&quot; am &quot;my&quot; feelings, and &quot;my&quot; feelings are &quot;me&quot; (i.e., emotions and self are the same thing). So if enlightened Buddhists claim to be free from illusion of self, and if emotions still remain and occur, how can that be explained as anything but dissociation (i.e., dissociation of a covert part of self from the overt rest of the self)? Hope that is clear enough.
In Iti 109 (quoted below), the Buddha indeed taught man to swim against his nature to become free from suffering. Renunciation (nekkhamma - subject to the middle way) is against the flow i.e. it's not natural to man. Craving is natural to man.

This was said by the Blessed One, said by the Arahant, so I have
heard: &quot;Suppose a man was being carried along by the flow of a river,
lovely &amp; alluring. And then another man with good eyesight, standing
on the bank, on seeing him would say: 'My good man, even though you
are being carried along by the flow of a river, lovely &amp; alluring,
further down from here is a pool with waves &amp; whirlpools, with
monsters &amp; demons. On reaching that pool you will suffer death or
death-like pain.' Then the first man, on hearing the words of the
second man, would make an effort with his hands &amp; feet to go against
the flow.
&quot;I have given you this simile to illustrate a meaning. The meaning is
this: the flow of the river stands for craving. Lovely &amp; alluring
stands for the six internal sense-media. The pool further down stands
for the five lower fetters. The waves stand for anger &amp; distress. The
whirlpools stand for the five strings of sensuality. The monsters &amp;
demons stand for the opposite sex. Against the flow stands for
renunciation. Making an effort with hands &amp; feet stands for the
arousing of persistence. The man with good eyesight standing on the
bank stands for the Tathagata, worthy &amp; rightly self-awakened.&quot;

The author (Richard) quoted by the OP portrays Buddhism in a negative way, probably in an attempt to peddle his own teachings (called &quot;actual freedom&quot;?) - at least I guess, from some contents on the website.
From this page (quoted below), we can see Richard's teachings, from which I gather that &quot;actual freedom&quot; is the freedom to enjoy life fully (i.e. indulge in sensual pleasures without limitation):

Taken to its extreme, as Hindu and Buddhist philosophy does, one
denies that this planet earth and the space that it hangs in – and the
universe itself – are actual. To them it is all an illusion, a dream.
For them, the ‘Dreamer’ – their god – is who ‘I’ really am and all
their effort is predicated upon realising that this is who one really
is. Westerners have foolishly allowed themselves to be taken in by the
apparent wisdom coming from the eastern mystical states of being
because of the paucity of experiential wisdom in their own culture. It
all started growing exponentially after the sixties generation trekked
to the Himalayas, and to other exotic places, to find the permanent
drug experience ...
One arrives in the actual by becoming involved, totally involved in
being here ... not by practicing detachment. Being here is to put your
money where your mouth is, as it were. All other actions are methods,
devices, techniques ... in other words: delaying tactics. In being
here one is completely immersed. Being here is total inclusion. One
demonstrates one’s appreciation of life by partaking fully in
existence ... by letting this moment live one. One dedicates oneself
to the challenge of being here as the universe’s experience of itself.
...
Meanwhile people thoughtlessly pursue the elusive chimera of Eastern
Enlightenment.

The Buddha realized that modern day hedonists like Richard, who delight in attachment, is excited by attachment and enjoys attachment, would not be able to understand the Dhamma (teachings of the Buddha) as we can see from SN 6.1 (quoted below):

&quot;This Dhamma that I have attained is deep, hard to see, hard to
realize, peaceful, refined, beyond the scope of conjecture, subtle,
to-be-experienced by the wise. But this generation delights in
attachment, is excited by attachment, enjoys attachment. For a
generation delighting in attachment, excited by attachment, enjoying
attachment, this/that conditionality and dependent co-arising are hard
to see. This state, too, is hard to see: the resolution of all
fabrications, the relinquishment of all acquisitions, the ending of
craving; dispassion; cessation; Unbinding. And if I were to teach the
Dhamma and if others would not understand me, that would be tiresome
for me, troublesome for me.&quot;

The Buddha felt it was too troublesome to teach the Dhamma to people like Richard, but he was persuaded otherwise. And we are fortunate and blessed because of that.
If people like Richard feel that practitioners of Buddhism are gloomy, &quot;anti-life&quot; (quoted verbatim) and do not have &quot;genuine freedom, peace and happiness&quot;, the answer to this comes from Dhammapada 197 - 200 (quoted below):


Happy indeed we live, friendly amidst the hostile. Amidst hostile men we dwell free from hatred.

Happy indeed we live, friendly amidst the afflicted (by craving). Amidst afflicted men we dwell free from affliction.

Happy indeed we live, free from avarice amidst the avaricious. Amidst the avaricious men we dwell free from avarice.

Happy indeed we live, we who possess nothing. Feeders on joy we shall be, like the Radiant Gods.