This happens with (theoretically) non-profit insurers, too. Like the BCBS networks.

I nominally agree with this sentiment. BCBS does have issues like this happen, but not at the same level others, in my experience.

Anecdotally though, I've found that my current insurer (United) denies and delays care far, far, more often than when I had a similar plan with BCBS. And I'm not talking about small bills, my son was in the NICU for 41 days, at a cost of ~$150,000. Through BCBS I paid like a grand of that. United denies the most random things, a referral to a specialist, meds for on brand usage while they'll pay for other meds that are off brand, for instance.

I do have a platinum level plan, I am _extremely_ lucky to have this. I know the vast majority of Americans, most of my friends and family, fight with their insurance companies for far less than my complaints.