Nuclear is getting drastically cheaper as of late, and will likely continue to do so. Power infrastructure should not operate to turn a profit, but to provide a service. Nuclear does not take drastically different power infrastructure than current fossil fuels. Radiation is genuinely a non-issue. Waste can be stored in seismically inactive rock above the water table and be essentially ignored forever. Coal causes far more radiation contamination, by orders of magnitude, than nuclear, not to mention there has been barely any nuclear energy incidents, and we only know so much about the ones that did happen because of fearmongering. If water temperature is affecting the local rivers, the plant is mismanaged and poorly designed. My local plant only draws water from its own artificial lake, and does not affect the environment. In fact, it's lake and the surrounding area was turned into an excellent park, where I hike often.
The reasons why nuclear makes a ton of sense, at least right now:
- Power storage technology is not ready for 100% renewables on most grids, so some level of base power needs provided
- Nuclear can replace existing fossil fuel plants, since they provide nearly the same service
- Renewables are not available everywhere. In places where the solar flux is too low for significant parts of the year, both wind and solar can suffer. If the power grid is entirely reliant on them, this could cause catastrophe. Nuclear bridges that gap without affecting CO2
- Nuclear is already nearly at the point where plants can be built on-site for power supply on power hungry infrastructure with relative ease, and is only getting better and cheaper.
- Until we have other options and better power storage, some base load power is necessary, and nuclear is infinitely preferable to fossil fuels
Nuclear won't be a forever solution for large grid power, and will eventually be replaced by mature renewable infrastructure. That time is not going to be in the next decade, or even two, most likely. In the temporary, it can largely replace the fossil fuel industry that is killing the planet. In the long term, on-site reactors will allow power hungry infrastructure to avoid affecting the local power grid, like research institutions, large scale manufacturing, and data centers. You're totally right in that renewables are far preferable to nuclear, but they simply aren't swap in, swap out replacements for each other. Nuclear isn't really competing with renewables, it's competing with fossil fuels. They're both critical parts of what we need to get off fossil fuel dependence.
Edit: For the record, coal plants can take upwards of 8 years to construct and typically multiple decades to "break even." We don't operate power infrastructure because it's profitable, but because we need it.