Re: .. not really
"You have highly radiotoxic long lived contamination to consider as well as radiation."
Correct me if I am wrong, I had to look it up, but radiotoxic implies direct contact with, inhalation or ingestion, does it not? I.e. basically a poison. I was aware of the effect, if not necessarily the term.
How does that apply to stuff that's buried and vitrified/sealed in concrete in remote areas? Especially places where, for the first 100-200 years care needs to be taken to avoid radiation? You'd expect that containment procedures sufficiently advanced to cover radiation hazard would preclude people getting into direct contact. We're not talking DU shell dust from A-10 gun runs poisoning locals in past battlefields here.
The claim that we've done all we could with reactor tech strikes me as a bit disingenuous as well. I will happily grant you that current reactor tech and deployment is severely flawed. But the fact remains that very little actual new designs have been built in the last 10-20 years in the West. The system in Finland comes to mind, and while it supports your point, it's also one of the very few data points.
Bit like if we had frozen jet engine usage at the turbojet level and had never gone on to turbofans, except for theoretical schematics. I would be skeptical with a "we've fixed it" claim coming out - the industry has had many of those - but dismissing it as a hopeless dead end seems quite risky at this point in time.
And a lot of the costs are not purely technical in nature, but have to do with financing during protracted legal challenges and the lack of standardization.
We don't know how climate change will progress, but all indications is that it trending at least slightly worse than had been expected only 10 years ago. While renewables are certainly following an encouraging trend, I have yet to see totally convincing proposals about how we'll move to 100% renewables and handle both short term fluctuations (for example, no sun at night) and, more importantly, long term seasonal variations (California Dept of Energy says they get only 20% as much wind+solar in the winter as at summer peaks).
What we want to do is to have as many plan Bs as possible to cover contingencies for the next 100 years. Fission is one possibility, fusion (hah!) is another. So are large scale solar farms nearer the equator in desert areas. Being dogmatically opposed to nuclear energy vs being healthily skeptical of it, is not something I will be voting for any time soon.