RESOLVED (1026/2023)
I had the same issue with my 2021 Jeep Grand Cherokee with UConnect. I tried 5 cables all known good Power/Data cables.
finally, someone suggested the following and it works!
1. Turn off your phone (Power Down)
2. Make sure Jeep is also off - this might apply to other vehicles with Uconnect
3. Plug phone to jeep USB PORT
4. Turn on Jeep. My phone powered up and Said "carplay finished setup" or something like that
Now you should see Uconnect in the carplay configuration under settings -> general -> carplay..
Sometimes I have to unplug and plug phone back in but this has been working all day