Yup 2018 as well and compared to other people thankfully my head unit hasn't been as bad. It only resets itself like once a month.Sounds like Jeep needs to replace the entire head unit in his JL.
I had a similar thing happen to my 2018 Subaru and it's top infotainment system, and a similar series of dealer attempts at resets and software updates and saying they tested it before it started hiccupping on the drive home from the dealer and I couldn't even call them while driving. On the 3rd visit they gave up and installed a new head unit. That fixed it.
I don't have much time with it anymore though as I should be picking up my new Jeep tomorrow! Fingers crossed on the head unit/overall quality. I am pretty excited to get it.