I asked Signal motivations for SMS removal
I think you're forgetting the main reason: the group of people using it to communicate is really small and shrinking every year.<p>The only large group of people who still primarily use SMS to communicate <i>person-to-person</i> is Android users in the USA.<p>Every other country has settled on either Telegram, WeChat, WhatsApp or FB Messenger, or other niche apps. These apps work on both iOS and Android and often also Windows. I haven't sent an SMS in probably 12 years. I don't know anyone who has.<p>It's only in the US that iMessage is so prevalent that Android users have to use SMS, the only other way of messaging iOS devices. And the US is quickly becoming a de-facto iOS only country. It already has more than 50% market share, even 80% among young people.<p>With the US going (almost) full iMessage and the rest of the world having already settled on another app there simply no point to supporting SMS.