I'm a bit doubtful of this. It's possible but Microsoft uses Live for both business and gaming, but they've only had a track record of forcing Live account adoption onto users in the gaming sphere. It may happen, sure, but I don't think it's likely.
That all said I didn't think it was likely that Minecraft would switch over to using Live accounts since Minecraft is so famously cross platform and Live accounts have struggled with that in the past.
They're also boiling the frog on Windows local accounts at the moment. It's no longer possible to set up a new install of Home, or Windows 10 (any SKU) in S mode with a local account without either disconnecting internet during installation or going back and converting to a local account after
Mojang users required to move to Microsoft (formerly Live) accounts: 2021 (https://www.theverge.com/2020/10/22/21527647/minecraft-micro... )
I expect the same will happen for github eventually. Given the were acquired in 2018, by this timeline, I'm guessing by 2025.