[acdha]

… and those markets have a long history of being gamed despite enjoying much larger numbers of people who can check the work. The drug market is huge and extremely lucrative which ensures that any successfully started review service would be under attack from multiple fronts – lawsuits, attempts to hire people away or buy influence, setting up “competing” groups which try to sound legitimate but exist only to attack the other group’s claims, etc.

Read the history of what happened with say the financial ratings companies during the 2000s for one side (regulatory capture) and the tobacco or fossil fuel industry for the dirty tricks version. There's no reason to think that wouldn't keep happening, all of which dramatically increases the cost and likelihood of failure.