Further, there were big political and financial reasons to push the vaccines through. Those are all conflicts of interest. Pfizer had millions of doses manufactured before approval. If trial results didn't look good, they certainly had the incentive to "massage" the results to get it approved and get those millions of doses sold rather than a huge loss.
As the original poster shared, it should be a considered a reasonable position to be skeptical of small scale results. Pfizer's position appears to have scaled well (Moderna as well). 100s of millions of doses across diverse populations show its relative safety and efficacy.