How do I appeal a ban on matrix?
Please include the room and the reason for the ban.
I don’t think I was ever in an gnome.org room 
Then there’s nothing we can do.
okay, it’s a pitty that you don’t want me to be a part of the gnome community.
But i will respect your decision.
GNOME does not control what happens in other Matrix rooms; if you got banned elsewhere, there’s nothing the GNOME mods can do about it.
Do the “other Matrix rooms” dictate you who is allowed to be in your community?
Yes, if the ban is shared in a list.
Find out where you were banned, and ask them to lift the ban; then you’ll be able to join GNOME rooms.
I won’t do that, because I was banned because I criticized that matrix.org only add spammers to their ban list and don’t deactivate their users which leads to an unhealty matrix network especially in unmoderated rooms. (child porn in rooms for month despite reported and so on).
I am a moderator of tchncs.de and in my opinion is, that a server should take care of their own users. I take reports seriously. Because “Our Users, our spam”
BTW we used the list, too.
We switched to https://matrix.to/#/#community-moderation-effort-bl:neko.dev which is a spam only list.
Because most communitys want to decide themself what is bad behaviour. Every community has another etics
Some are okay with criticism, some not. And so on.
But I accept your decision, that you don’t want me to be in your community.
Thanks for the Information.