Name one time in the entirety of recorded history when "the decentralized market of ideas" did anything of the sort.
This is literally how most scientific progress is made.
Science absolutely does not work by just letting everyone believe whatever they want and somehow just expecting the truth to "win."
What you don't see here, for example, is any mention of a "President of Science" or other committee making that call, nor particular suppression of lines of inquiry.
Linguistics being an example where ideas about grammar are only accepted because Chomsky is still around forcing everyone to accept them; AI language models don't seem to follow them.
You're right, though, public vaccine discourse would have been significantly better if we required internet research experts like Joe Rogan or any of the talking heads on Fox to have a PHD in immunology or epidemiology or at least a double-masters in biology and economics before we allowed them to speak to more than ~ten people at a time.