> if i loose my access to github i only loose access to my github identity but i don't loose access to my code, so i can live with that.
That means that you need to fork your own project, and there is no way to communicate it to the users, since the new account could just be someone pretending to be you.
If there is a security vulnerability, it would remain unfixed forever.
> is it more likely that someone will break into my account and abuse my identity if i don't have 2FA or is it more likely that i loose my second factor and have to rebuild my identity
Since phones are very easy to break, and until very recently there was no way to backup google authenticator, I'd say that losing your 2nd factor was the most likely of the two.
Now if you say that you backup your 2nd factor seed in your password manager, where your password is… congratulations you're doing over-complicated 1 factor authentication!