I highly disagree with this assessment.

First, addressing your first point. Yes, they are stopping development of some core AOSP apps, but we are talking about apps which have had very good, oftentimes way better, alternative FOSS applications anyways. I really don’t see this being an issue at all.

For the second and third part. Google can sometimes do this with their core apps. Sometimes I suppose but GAPPs works on pretty much any custom ROM I’ve ever tried it on. Whether it be open gaps or microg. If you’re talking about things like Google Play Certification and safety net, I also disagree there. It’s a tool that Google provides if application devs don’t want to use it they don’t need to. Many devs DO want it. That’s not Google’s fault.

Application developers want, and sometimes need this level of security. Regardless of what anybody says, attestation is indeed a critical part of security.