Local radio in small markets is unbearable. Most medium markets too. But there is lots of bad radio on the SiriusXM channels too.
Commercials aside, I don't think most of SXM channels are up to the same quality as the equivalent stations in say LA. KIIS is better than Hits 1. KROQ is better than Alt Nation. Power is way way better than The Heat. Quality of program directors, music scheduling, personalities, but mostly just care and attention. They might be in the same ballpark as Houston, which is probably the weakest of the 10 major markets.
Of course a lot of the SXM channels have no terrestrial equivalents.