There seem to be a MAJOR problem with your reasoning.

Why do we fear carbon emissions? Because climate change will make swaths of planet uninhabitable and/or underwater, forcing people there to move.

Don't tell me your solution is preventively moving half billion people. Isn't that the result you wanted to avoid? What's the principial difference anyway between land becoming uninhabitably hot and land becoming uninhabitably cold (due to lack of heating)? You lose land either way and have to move people from it, worsening situation everywhere else.

Your solution is basically shooting yourself in the foot to avoid gangrene, and the amount of faith you have in such solution is disturbing. Your position is one big reason why climate change deniers exist: because you scare people with your misdirected zeal.

But there is now 7 billion people. And no, it's not just "People will have to move": +6 degrees in one century is a temperature change we haven't seen since humans appeared on Earth: https://www.xkcd.com/1732

So we need to come back to emissions of 1990 (when they balanced natural absorption), emit a even less for a while, but with 7 billion people, everyone has to emit much less than in 1990.

To preempt any question... I still eat meat and I don't see how I could do without.

Then stop talking about crimes about humanity. If you consider yourself a criminal, go and jail yourself.

Personally I don't think "going back" is viable, we should probably be trying to engineer ourself a new climate. Better than we had pre-industrialization.

Our planet was pretty messed up even before humans came. It was going to snowball.