Concerned about SRAM SX Eagle I am currently looking at 2 hard tail MTBs, namely the Grand Canyon MTBs from Canyon, especially the

Grand Canyon 7.0 and...
Grand Canyon 8.0

and the difference seems to be 200 EUR which translates into the following major component differences:

SRAM SX Eagle vs Shimano Deore XT rear derailer
RockShox Judy Silver vs FOX 34 Rhythm fork
Rapid Rob wire-bead clincher vs Nobby Nic folding clincher tires (tubeless ready)

Now I have seen some posts on MTB forums and on Youtube that seem suggest the SRAM Eagle SX derailleurs fall apart very often and are very flimsy and unreliable, because they appear to be made out of plastic. The hate towards SX Eagle seems to be very strong on the forums. This got me worried, so I cancelled my order on the 7.0.
Does anyone have experience with the new SRAM SX Eagle 12 speeds?
Is it really that bad?
The exact spec differences:

Rockshox Judy Silver vs Fox 34 Rhythm GRIP

GRIP refers to the variety of damper, an IFP type

Rockshox have a similar damper type, which is called the Charger R or Charger RC, on some of its forks but not on forks like this.
Rockshox Judy refers to a 30mm stanchion with 'boost' spacing, and Silver means 'steel stanchions'. Note that 30mm vs 34mm means that the Fox should be significantly stiffer. In addition, it has the 'TK' or Turnkey damper.
TK damper is an unsophisticated design, which comes below the 'MotionControl' damper which itself is below the Charger R/Charger RC design in Rockshox line-up.
This is Turnkey:

Whereas this would be MotionControl, which these forks can possibly be upgraded to by changing the internals (but you'd need to check, as Silver is steel and has a different thread pitch to aluminium Gold)

The drivetrain spec is completely different:

SRAM have their 'low-cost' 11-50t cassette for HG freehub https://www.sram.com/en/sram/models/cs-pg-1210-a1
Shimano have a full 10-51t cassette for all their 12-speed drivetrails (11-51t is relegated to 11-speed).

Because of the cassette differences, the Canyon 8 has a newer freehub design, Shimano's Microspline design, which is better designed when used with lightweight freehubs made of aluminium - the HG design tends to suffer damage when the freehub is made from aluminium. Therefore the MT410-B is likely to be more durable than the MT400, even though both are constructed in much the same way. Microspline is also required (or SRAM's equivalent) for use of cogs smaller than 11t. https://bike.shimano.com/en-EU/technologies/component/details/new-tech-microspline.html
If you went with the 11-50t system then you'd not be able to upgrade to 10-50t without replacing your wheel or freehub. So 11-50t here is inherently a cheap-out given that the Eagle system is designed around a 10t small cog.
As you say, there are many reports of SX Eagle snapping in the upper knuckle, whereas Deore XT has a good reputation, and compared to cheaper derailleurs it uses sealed-bearing jockey wheels, which will have longer service life than cheaper ones.
As far as the tyres go, if you read the spec more carefully they are in fact Rapid Rob on the rear of the Canyon 7, and Tough Tom on the front.
These are OEM parts https://www.schwalbe.com/en/mtb-reader/tough-tom https://www.schwalbe.com/en/mtb-reader/rapid-rob which are designed for low cost.
Both of these have fairly minimal tread, though they are not said to have great rolling resistance because cheaper tyres will tend to use fewer different rubber compounds compared to more expensive ones, though it's no issue to change this.
The Canyon 8 has a Nobby Nic SnakeSkin Evo at the rear and a Nobby Nic Performance at the front.
https://www.schwalbetires.com/bike_tires/off-road_tires/nobby_nic_hs463
'Evo' refers to Schwalbe's highest-quality range, using three different rubber compounds, whereas Performance is a cheaper version. According to Schwalbe's specs, Evo has better rolling resistance, which is more important on the rear of the bike. This tyre is one that does not need to be upgraded, although some people might replace it for something with more or less tread, depending on their riding style.