Main problem was that FDA set too high of a target for tests compared to PCR, iirc it was around 80%, where did they get that number is unknown. There were companies that had rapid antigen tests created back in February (fx E25Bio) which had lower sensitivity, so they were spending all that time to reach the goal, while also forced to make test more expensive. And main problem with that FDA mindset is that accuracy is not random, it depends on amount of viruses in the person and for people who were transmitting the decease accuracy approached 100%, and that's what we care about from the pandemic standpoint.
There's a video from MedCram where co-founder of pharmacy company talks about it in more detail: https://www.youtube.com/watch?v=qKM4MIrfr4k
Tests can be properly regulated and checked by FDA, but if they set target with more thought behind it and acted quickly back in February and we had cheap 15 minutes tests, we wouldn't be in current situation now.