I work for a small org, joined when it was like.. 7, now we're ~50, and fully remote. The where doesn't matter, but the when does for us. We still exploit synchronous communication quite heavily.

Yes i know some orgs can async everything. Some people prefer it. You could argue many cases on why async makes for a more mature interaction process, more efficient, etc. However we have not managed it. I'd say largely 50->80% of our communication is sync, and i don't see anyone advocating for changing that with us, despite having basically fully flexible hours and a global team.