It’s a Sonos issue, there are other threads about it. Keep an eye on the Release notes thread, where they’ll announce it when it is ready. There is currently no predicted date, it normally takes several weeks, I assume for testing purposes.
Well, they could update the corresponding site (http://faq.sonos.com/trueplay). If I read that, after the failed trueplay sends me there, I'm to believe the iPhone 12 should work. So then I start thinking, what am I doing wrong? Just one line “TruePlay is temporarily unavailable in IOS 17 and higher” would make all the difference.
But no, pretend like there's nothing wrong.