Gregory's Server
From a technical standpoint this is correct, if ppl would use the right Extensions as a collective minimum, but this will just not be the case until ejabberd etc. that these Extensions are the minimum and that they will not communicated with anything that has less.
And there is still the problems with clients, which would need to become really good for sticker (packs), voice messages, gifs, many images and videos and good search.
The XMPP clients i used back then where really fast and i liked them a lot to write with 3 friends and a bunch of bots but i think today, since facebook messanger, telegram and snapchat this is just no option anymore for it to be widely adapted.
@m
I've been playing around with Snikket as a potential way to get more people trying XMPP. Have you any views on it?
For what it's worth, the default Snikket app has OMEMO on by default, voice/video calls and voice messages, plus image/document/location attachments, but it doesn't have stickers or GIF pickers.