A friend of mine asked for some help with a design of speaker-stands, 3 thick bits of wood formed into a Z shape, but what angle to cut? That fairly quickly reduced to solving a quadratic, but how to solve that? This was pre-internet, I'd done the derivation at school but that was a while ago, so I spend 2 days working the sod out. I enjoyed it so much that I went to the local University and asked if I could get on the maths degree program, they said yes. That changed my life.
I'd had a GH account for ages under my own name, I closed that as soon as Microsoft took it over, moved all my repos to GitLab, good move. I opened a new GH account under a silly name [1] so I could collaborate with people still on it. Now I'm not really against 2FA, but don't use it myself, it adds friction, adds risk (what if you lose it), it seems too "theatrical" for my liking. You want to use 2FA? be my guest, live and let live etc. What I don't like is being told what to do with my account, particularly by someone like MicroSlop. I won't add 2FA to my GH account, so I'll not contribute any code to GH based projects, ho hum. As I understand it, I'll still be able to raise issues without 2FA, fine, and when 2FA becomes mandatory for that, I'll stop doing that too.
Lose what exactly? Decent 2FA setups make you confirm you've recorded a set of backup codes somewhere (they often recommend print and store in a safe, I find a secure note in a password manager works well) before activating it.
Furthermore plenty of TOTP applications offer secure backup and syncing features.
So again, what specifically do you think you're going to "lose"?