in very general terms there are a few truisms about energy: economic growth and technological progress both seem to be very much correlated with energy consumption; modern democracies (eg the "Western world") are in gridlock and have increasingly become very myopic, short-termist, incrementalist with regards to energy policies (and others too, but that's not strictly relevant here)
so any advocate for any kind of energy policy preference is fed up, frustrated, and so on.
green advocates? yeah, completely right with regards to global warming, ecological disasters, fucking up the planet, etc.
based on one's morality we can say that advocates of global fairness are right in their view that currently the "West" has the burden to exert a heroic effort to fix the warming they caused, and help the poor countries to skip the "fossil phase". and anyone pointing out that this effort is basically non-existent is also right. (and so poor countries will be likely more affected by climate change and economic and energy shocks than rich ones. mostly because being rich helps with almost everything, and also because poor countries tend to be located in areas that used to enjoy year-round warm climate with occasional extremely warm days which will now become a lot more frequent)
on top of all this poor countries usually doesn't have the luxury of picking the best long-term solution. (but as we saw even rich countries have been optimizing for short-term nowadays.)
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okay, that said, economics of nuclear energy, it all depends on economies of scale. it's basically irrelevant what happens with 1-10 power plants.
if in a given country there won't be a healthy nuclear energy industry, then keeping one plant alive is .. irrelevant. (even if economically retrofitting a 40-50 year old plant is cheap, because the big ticket items are already paid for ~40 years ago.)
renewables got cheaper because they are mass produced. were nuclear plants mass produced they would be drastically cheaper too. (that's the promise of small modular reactors.) but even simply ordering 100+ big plants would push down costs from the ~3rd one. (if they were properly standardized and near identical. it parts were pre-fabricated, and so on.)
basically construction (so housing and transportation ... and healthcare and education) everywhere is getting more and more costly because technological progress is unevenly making other things more cheap. (and also our standards are going up, so we use the old inefficient technology and more skilled labor to build better things, it'll be simply more expensive.)