Ha! I posted the same in https://itch.io/t/4182603/io-eventual-disappareance haha. Will delete it there so there is no double topic, so here is a copy of what I had wrote (pretty much the same questioning):
.io eventual disappareance
According to https://every.to/p/the-disappearance-of-an-internet-domain :
[…] these rules […] will soon apply to the .io domain. They are firm, and they are clear. Once the country code no longer exists, the domain must cease to exist, too, ideally within three to five years. Like a tenant being told that their landlord is selling up and they must move, every individual and company who uses a .io domain will be told the same.
That’s years away, but that’ll apply to itch.io!
So just starting a discussion about it :)
Branding wise, I guess it could be just “itch”.
Domain wise though, there will have to be some sort of transition to something else.
Not that many straightforward “itch” domains are available, and many are parked like itch.games and itch.com and itch.net. At least itch.io already owns itch.zone, so maybe that might become the main domain?