Yeah, I'm currently insured by United and was previously insured by Blue Cross.
I think your point is correct that the site is a (now cliched?) "leaky abstraction." But the good news is that it works for at least some segment of the market (those like myself).
I was 25 when I did the Blue Cross app and 27 when I did United.
Did you fill out complete applications for Blue Cross and United? Were you presented with a sign-on-the-dotted-line contract with a rate on it?
Were you applying solely for yourself?
Again, if you're in your 20s, healthy, male, and alone, you are very easy to insure, because you cost epsilon for Blue Cross to insure.