> On the whole there is a lot of good stuff, but I worry about the ability for it to stay an open standard. Today Google has dominant browser market share with Chrome, so they get to dictate new web standards just by building them into Chrome.

I think this concern is mostly obviated by the use of content schemas ("lexicons"): https://atproto.com/lexicons/atproto-com

My concern is how many of these schemas will need to be implemented for true compatibility. At this stage at least, it's still better than implementing ActivityPub.