Okay, you first.

I'd much rather find a way to maintain people's lifestyles, reduce emissions (and make it even better in the process).

It's not "you first". There are perfectly good replacements available, we just need governments to invest heavily on replacing them instead of using that money to maintain the status quo.

I've already substantially changed my lifestyle to be more sustainable.

I don't own a car, I don't eat meat, I consume very little and try to buy used things instead, I repair all my things as much as possible, I try to steer my investments away from anything close to fossil fuels.

Now you.

I do everything you just listed. But that was by choice, and I know people who won't want to e.g. ever give up eating meat.

We have to accommodate these lifestyles (and build tech to make it more sustainable) - people generally don't want to go 'backwards', even if you or I don't perceive that as a problem.

Ultimately it's irrelevant, because both of our lifestyles are still heavily carbon negative without offsets. We both own a computer or live in a house I assume? That's why I'm sceptical of the "just live more sustainable" movement.

Oh, i didn't miss that part, i think you may have missed my assertion that Energy is crucial to flourish. One may see a society "Flourish" by innovating their way out of an unsustainable path.

Everything we consider advanced tech today is built on an economy made possible by vast, cheap and accessible energy sources such as the ones we're dissing.

I agree that we need to stop using energy sources in a way that threatens our existence. But i assert that there are massive benefits we have to be thankful for as well.

Our lifestyle is sustainable. It just doesn't scale for 10 billion people. The only problem what we have is the amount of people. We can do something against it, but we won't.

Why can't it be both?

what both? Any existing prediction says that the Earth won't support more than 10 billion people. Our life is much more "sustainable" now than before. Yes we still have a lot to do, we will always have, but gosh, we are simply too many. I can't believe in a COPXX if birth control isn't part of the solution.

Both population control and a sustainable lifestyle.

you are right. Was Population control a topic on COP26? Is population control a topic when we talk about CO2 emission?