Oil companies paid to form that opinion in the public.
>no Chernobyl
Chernobyl was the result of a HIGHLY unauthorized, and stupid experiment... phenomenally stupid. So many red flags were driven past at high speed.
The reality is to cause the issue, the operators had to drive the reactor well into a dangerous and hard to control regime which it would not get into under any normal operation circumstance.
So while yes, it shouldn't have been physically possible to do it, even with that design it took substantial, deliberate malfeasance to get that result (you can also only get that result with that design - a meltdown is not normally an explosion).