In any fission reactor. Those are going to be true no matter what the design is. Those are always going to carry with it serious safety issues, not to mention huge expenditures those issues entail.
That mathematical model is taking all of what you said into account. It's absolutely fair to look at all the reactors in operation and not just the new ones. If you threw out the newer ones, wouldn't that be grading on a curve? It's easy enough to separate the newer reactors from the older ones, do the division to find out if there is improvement.
It might give you confidence, but that method is also invalid due to shorter operation times. You can't extrapolate improvement in the long term from the short term, especially when long term retrospective safety was exactly what this study was meant to find out. The scientists know this, and I'm informing you of it.
Moreover, just because the article doesn't mention that the scientists studied new reactors doesn't mean they didn't, however flawed that analysis might be. Reporter can't put everything into the story. Maybe you should read the original.
I seem to remember operator stupidity was actually what caused Chernobyl, and the reactor wasn't designed with withstand the utterly stupid things done. In the last decade, it's become fashionable to say it was a design flaw. No, it wasn't. True the reactor wasn't designed to be run in an idiocracy. No reactor can be. Not when every reactor has to be constantly cooled to prevent catastrophe.
A principle selling point of the old reactors everywhere by the industry in all its ideologies and nationalities was their safety. Now we have new, improved, reactors whose selling point is their safety. Given the industry track-record, worldwide, why should those assurances be considered true? Are they born again honest and humble this time? Don't you see a credibility problem?
The current reactors are considered improved by correcting yesterday's problems, not any new, unforeseen ones. New designs can introduce new, unforeseeable accidents.
The only way we can know if they're significantly safer is to run them long term. That hasn't happened yet. To sum up: you have no reason but industry assurances and blind faith that the new ones are safer. And no reason to think these scientists approach was simplistic or biased just by reading this article.
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