And that is probably are IPv4's flaws, not BitTorrent. If everyone switched to IPv6 then they can connect to each other without using NAT, because IPv6 address space is so big everybody on earth can have their own unique IP address.
On IPv4 you don't know if your packets got dropped because of your firewall blocking some ports, or because ISP's CGNAT get overloaded and decide to drop your packets (and customers can't do anything to fix that)
I agree, but there's no way my mom could figure out IRC on her own. She uses Dropbox daily, though.
E.g.
https://kiwiirc.com/nextclient/irc.libera.chat:+6697#irc
https://web.libera.chat/?channels=#irc
There are also mobile apps with better persistence and even simpler interfaces.
IRC will never take over the world because:
* The protocol is missing some minor but important UX-enhancing features. This is fixable, but there's nothing valuable enough about the existing userbase for a capitalized entity to bother working with the entrenched groups. And non-capitalized entities move relatively slowly.
* There is no profit in it -- the corps who want to own messaging want to own messaging. This is a great idea for them, but a terrible idea for users.
* IRC networks don't want Eternal September to happen to them. Not that anyone is beating down their door.
Too late for that. In late 90's/early 00's, you had web clients for IRC.
IRC doesn't even support basic text formatting, let alone links, images, emojis, threads, etc.