I recently switched to FairEmail. It’s a really nice app and works much better than anything else I’ve tried. And it would be a shame if it were abandoned.
On the other hand, I have published a few things to Google Play myself. Google has made constant effort necessary to keep up with their policies. It wasn’t worth the trouble for someone like me who just casually released things I built for my own use. I can’t blame anyone else for deciding to step away from it either.
It is appalling that he also has to deal with abuse and threats for performing a public service.