Exactly... It wasn't until the 4th or 5th comment by someone else after the initial post that Wireless was even mentioned. This thread started in September, right around when the iPhone 11 Pro and Pro Max was released. The common denominator here is the phone and/or iOS 13, NOT Wireless specifically. And the reason there's so much focus on the Mini Cars here is that that's what was reported in (I think?) 9to5Mac or whomever it was.. Because the initial poster here noted that was their hardware. And at the time we were still on page 1 (now we're son page 18!).
The CarPlay screen works in that you provide access to your Lock Screen (over USB or WiFi/BlueTooth) and the Stereo screen is activated yadda yadda yadda... From all of my troubleshooting, the problem seems to be that THAT connection drops off over X amount of time. From my experience, it's been roughly 2-3 minutes. And again, as I posted earlier, I'm also seeing disconnects with data transfer while connected to my MacBook Pro after the same amount of time. In both cases with my Car and my MBP, the Phone continues to get a charge, but nothing is transferred thru the cable. I've tried new cables, switching 'em around (like that should matter with a Lightning Cable), I've even checked that the option to allow access to USB Accessories when locked is enabled.