Anecdotally, many people I know who used an antigen (rapid) test have experienced false negatives. PCR appears to be the only way a positive COVID result is found.

It seems odd that the CDC updated this new recommendation and explicitly called out an antigen test is what one should use after the 5 day period of isolation.

It isn't odd at all. Many patients continue to have positive PCR tests for a long time even after the infection is cleared. PCR tests merely indicate the presence of viral genetic material, not necessarily infectious virions.

I took 4 at home tests, all said negative, but I was definitely sick, scheduled a PCR test, 6 days after my symptoms started was the soonest I could get an appointment for, and it finally confirmed that I had covid. 2 different brands of at home tests kept telling me I was negative.

So, I don't doubt the anecdotal stories of people getting false negatives with the at home. My coworker also took 4 and only 1 finally showed positive in the end.

So four tests say no and one says yes, and you believe the one? Maybe you just had a cold.

If the one is a PCR test, then yes you should trust the PCR.

Dr Michael Osterholm has covered at great length what garbage the rapid antigen tests are.

Different tests have different purposes. PCR tests have fewer false negative results when used to confirm infections in symptomatic patients. However, PCR tests are mostly useless for determining when those patients have cleared the infection and are no longer contagious.