There may well be tens of thousands of deaths from Chernobyl. No, we can't state that these deaths absolutely occurred/will occur -- they are spread throughout large populations, mixed into the vast number of naturally occurring cancers -- but technology regulation is not like criminal prosecution where things must be proved beyond reasonable doubt. Technologies are not innocent until proven guilty.

That depends entirely on the technology, and who is paying who. Fossil fuels have been proven guilty of numerous sins time and again and are still relentlessly defended as innocent. Leaded fuel in particular enjoyed an undeserved benefit of the doubt. Food additives are another category of chemical with very permissive regulation, provided they don't cause lab rats to immediately keel over.

Technology regulation is unprincipled at best and outright corrupt at worst, and even with the most pessimistic estimates nuclear power has the best safety record per watt of any power generation technology (and it's not close).

Fossil fuels being bad is an argument for getting off fossil fuels, not an argument for nuclear in particular.

    "2 workers died in the blast.

    28 workers and firemen died in the weeks that followed from acute radiation syndrome (ARS).

    19 ARS survivors had died later, by 2006; most from causes not related to radiation, but it’s not possible to rule all of them out (especially five that were cancer-related).

    15 people died from thyroid cancer due to milk contamination. These deaths were among children who were exposed to 131I from milk and food in the days after the disaster. This could increase to between 96 and 384 deaths, however, this figure is highly uncertain.

    There is currently no evidence of adverse health impacts in the general population across affected countries, or wider Europe."

What you are doing here is demanding that the cancers actually be demonstrated, requiring that radiation be treated as innocuous until it can be conclusively shown it isn't. This is the mindset behind those ranting against the linear no threshold theory of radiation carcinogenesis.

But regulation doesn't work this way. Nuclear isn't something that must be presumed innocent until proven guilty.