[hef19898]

Well, that the whole community of nuclear scientists, engineers and operators ignored the design flaws of RBMK reactors was an indirect conclusion of the two late 80s investigation boards the USSR (!) put in place. Read the annexes to INSAG-7, you can even find the design bureaus and directors named in there.

The KGB blocking the refit of the RBMK fleet is a myth from HBOs Chernobyl series. Truth is rather different, Legasov was seen by the younger generation as part of the establishment that held back modifications, while he simultaniously managed to piss off said establishment. And without support from the rank and file, and some enemies with the higher ups, his career was shot. Compounded by serious health issues following the Chernobyl clean up. Less dramatic than a KBG conspiracy for sure, but still bad enough.