I've been using AA for more than 5 years, occasionally getting weird things happening. As the software is continuously being developed and improved, I regard AA as a work in progress. Still, my experience is good in terms of it working well 99% of the time.
I think much depends on the USB cable. My experience is some cables work well, others don't. Rule of thumb: use your phone's original cable as a preference. Then keep AA updated to the latest version - Google updates it frequently. Android version 10 and 11 have AA built into the OS: it's not a separate app any more. There's also a matter of your phone brand and model. Samsung phones have a good rep (my current S20 5G with Android 11 is a good testament) while others not so much (I also have a Huawei phone with Android 10 that does not play well with AA).
Also consider if any other app on your phone is the cause of a problem with AA. Maybe a conflict there (Spotify has had issues recently).
You can check on AA news including issues here - https://www.autoevolution.com/search.php?s=android+auto