It won't work. You can absolutely trim a lot of fat from the modern lifestyle, but then you'll be left with a residual. Meanwhile the developing world will keep developing and we have no right to order them to stop.
The idea that it's not possible is bullshit too, and it's still bullshit even if you ignore nuclear power.
https://landartgenerator.org/blagi/wp-content/uploads/2009/0...
Back in the 2000s there was a ton of discourse around peak oil. As part of that, I recall reading very detailed breakdowns written by actual engineers and scientists arguing why you would never have a mass-market EV with the range of a gasoline car and you would never be able to power more than 10-20% of a modern economy with solar power. I own two EVs, one with gas-comparable range, and California currently gets almost 40% of its total electricity (averaged across day and night) from solar, and climbing. There were whole books on this. I think one was called Power Down. It was all 100% wrong.
I also recall reading detailed analyses by aerospace engineers about how you would never have a reusable rocket, that it was simply impossible or would cost so much it wouldn't be practical. First stage reusability is now routine, and second stage reusability is coming.
Detailed breakdowns of why X is impossible have an incredibly poor track record unless they reduce directly to the laws of physics. Will faster than light travel ever be possible? No, and I believe that, because if it was it would mean a huge part of modern physics (not just relativity) is wrong in very bonkers ways.
There is no first principles physics argument for the limits this guy is arguing.
Of course if you imagine infinite growth on a finite planet, that fails. That's a trivial argument. But that's not happening, probably due to birth rates declining. The question I'm addressing is: can this civilization and its near-future extrapolation be powered without fossil fuels? The answer is yes, and again even without nukes. Throw nukes in there and it just gets easier.
IMO this is 100% ideology and is an example of what I call "problemism." A "problemist" is someone who uses a problem as a stalking horse for one and only one solution that turns out to smuggle in some kind of ideological or social agenda.
I see problemism as a dishonest propaganda technique. It's a way to sell the idea without directly selling the idea, instead using concern over some other thing to smuggle it in.
So you know I'm not just picking on the left: right now there's a big freak-out on the right about birth rates. The problemists there argue that it's why we need to get back to ultra-traditional family structures and take rights away from women. They're not interested in any solution that doesn't do that, because they don't actually care about the problem. They only care about taking rights from women.
This guy and those like him only care about degrowth as part of what is probably some kind of anti-industrial political ideology. If the problem could be solved without it, that would be bad as far as they're concerned, just like how the far right doesn't care about solutions to birth rate decline issues that don't involve reactionary social agendas.
Most of these people are anti-capitalists. Thing is, I don't mind that. I don't think capitalism is the ordained perfect system. But if you want to sell me on an alternative to capitalism, argue for it directly on its merits. The test is: if climate change and fossil fuel depletion did not exist, could you still make your argument for abandoning capitalism in favor of your system? If not, then you're engaging in "problemism" to sell bullshit. Because there is no physical reason that you could not drastically cut CO2 emissions without abandoning capitalism. A simple progressive carbon tax combined with cheap renewables could do it. We just lack the political will.
https://ec.europa.eu/eurostat/databrowser/view/road_go_ta_to...
In 2008, people and businesses were still buying new computers every year or two, printing everything on paper, buying physical media. I don't know anyone that does this anymore. I don't think that is a good proxy.
https://www.bts.gov/us-tonne-kilometers-freight
(a bit easier in table form as the graph does not aggregate accross all means of transport).