i heard that he doesn't support development. That made sense to me since it could look like a conflict of interest to have one of the biggest investors to also be funding something.

Actively campaigning against open source developers being funded is next level... Maybe he thinks the bitcoin foundation concrete needs time to harden before building the buildings. or he is MR EVIL!

All of them, or specific ones?

Saylor understands Bitcoin from first principles as well as anyone can, of that I am certain. That doesn’t mean he is right about everything, or that he is even sharing his true beliefs in public.

With that understanding, the only thing he would sell Bitcoin for, is something that can earn even more bitcoin.