It was criminal for way wait too long. If you look at the study of infectious diseases the aerosol transmission model has been discounted for way too long due to inability to “prove” it. If you can’t design an experiment to prove or disprove an idea that doesn’t make it automatically wrong. For example, the aerosol transmission model for influenza was flatly rejected for a long time, even when key scientists found it plausible and had some experimental evidence which wasn’t air tight. In covid’s case the CDC and other experts were grossly exaggerating their confidence that the aerosol transmission model was wrong. My partner was treating covid and in late 2020 after a lot of evidence indicated it was plausible, she still had infectious disease experts make fun of physicians for asking about aerosol transmission. They were grossly confidently incorrect about a theory that had no evidence on either side but had some plausibility (because similar diseases had aerosol transmission). Again, the way the community acted in an area of unknown where it was impossible to prove or disprove was very unscientific.
It was only over a year (with a lot of evidence) that the CDC said “aerosol transmission is maybe sorta kinda possible maybe”.
There are multiple ways to validate an idea, and sometimes you can’t design a blind rct. We know parachutes work despite never having proven it in an rct trial.