There is nothing wrong with the mindset of AMP. However, news publishers felt forced to start using Google's AMP HTML framework for their articles for SEO reasons while you could achieve same pagespeed results without AMP.
As a matter of fact, you could actually fail Core Web Vitals with AMP pages, despite both Core Web Vitals and AMP being part of Google:
- Core Web Vitals is part of Google's Page Experience ranking criteria;
- AMP is an HTML framework by Google.
AMP already became less important
It was never really clear if AMP came with any ranking benefits. Obviously, before Core Web Vitals, better pagespeed and user experience could result in better dwell time, bounce ratio, pages per session and session duration. But that could also be achieved without AMP.
And as Core Web Vitals entered the ranking-party, AMP got dropped as a Google news top stories requirement.
Why Twitter once started to link to AMP
Because of the often lightweight character of AMP equivalents of -for example- articles and blogposts, some social media platforms started to link mobile users to those AMP equivalent. This makes sense as a better experience when going to external links could also result in more trust in the social media platform linking to those pages. And users would also be more likely to return to the social media platforms, clicking on links to other articles.
This means users would spend more time on social media platforms, which could increase ad revenue as well.
Twitter now stops opening links in AMP
But this now comes to an end. In their developers documentation, they are now stating the following:
We’re in the process of discontinuing support for this feature and it will be fully retired in Q4 of 2021.Twitter Developer Platform
Unfortunately, Twitter's support document doesn't give a reason for the choice of not linking to AMP pages anymore.