Probably because the actual message is buried under a mountain of self-serving, AMP-praising buzzwords ("user-first," "well-lit," etc.). The post spends so much time patting AMP on the back that it's easy to miss the point that it's actually announcing Google's retreat from AMP.

If they'd taken the same message and presented it as "we hear you: forcing you to reformat your web site using our own format sucks, and tying your search visibility to your adoption of that format sucks even harder, so we've decided to stop doing both those things," fewer people would have missed the point.