So what if it's not perfect? Worst case of nuclear waste mishandling would still have milder repercussions compared to doubled, or tripled or worse CO2 levels we are subjecting future generations to. That will persist too long after profits from fossils stop.

Hard to discuss or persuade when you are comparing everything to some ideal, and one-sidedly moreover. Can we talk about real world alternatives. Hypothetically even doubling natural radioactivity background (and that would require total recklessness) would be better option if we could have avoided large part of CO2 output. Now nuclear is becoming moot as we have cheap renewables and batteries anyway.