In the meantime, what happened was everything else Hossenfelder discusses. The price of solar and wind went down, and the price of nuclear went up. By the time we could even begin to discuss nuclear, it stopped being a solution.
I concur with Hossenfelder's overall argument, and there's no reason to quibble about that point, except that people tend to paint environmentalists as hypocrites for not being gung ho on nuclear. Carbon isn't the only problem that faces the environment.
If that next generation of nuclear plants can contribute, fantastic. I'll assume that they're well thought out and well planned for, rather than being a massive boondoggle as some nuclear plants have proven to be in the past. But any argument that "nuclear will fix it eventually, so stop building wind and solar" is always going to be fossil fuel industry FUD.
"What speaks against it is that it’s expensive and ultimately not renewable."