iPhone 12 Pro and battery while using CarPlay

I'm considering upgrading my XS to a 12 Pro but the guy at the Verizon store told me the 12 Pro wouldn't charge while using Carplay on the Lightning to USB cable for my two cars (2018 Kia Niro, 2020 Kia Sportage). My XS doesn't charge as fast in the car as it does on my wireless charger (and I don't expect it to)while using Carplay with Waze and Apple Music. Anyone got any real world results for how much a 12 charges while connected to CarPlay plugging into a USB not USB-C port? If it's not charging or worse slowly draining while using wired carplay, then the phone is a non-starter for me and I'll stick with the XS.

Thanks!