Nuclear was phased out because of the potentially catastrophic risk as well as the unwillingness go provide permanent storage for nuclear waste.
Further, traditional nuclear power plants don't scale well, see the costs in France (even though it's not represented in electricity prices and this although France is already heavily invested in nuclear power plants), problems with heat waves/dry climate, as well as the fact that economic uranium sources are limited.
France is building new plants, planning close to 50, however the long term trend will be a reduced share of nuclear power in the grid, because old reactors will have to shut down as well, and renewable energy build out will shadow everything else.
This is in terms with the estimates in the IPCC report that cover cost and potential avoidance in CO2 emissions.
Personally, I see activists mainly going after the government's to implement a strategy to reduce emissions, but surely almost everyone doing this will call out plastic items and fossil fuel usage where avoidable. Rightly so, if this reduces tolerance for whatever program (doing what? Reduce emissions?), I don't see the problem there, but rather at NIMBYism, mis information and green washing. There's nothing wrong with going after these things.
I feel like you are more interested in preventing actions from being taken than shedding light on things that are missed - I hope I am wrong though and calling out hypocrisy of climate activists isn't the primary part.
