As someone that used to work on a TV app I wasn't surprised when focus issues were the first thing mentioned. It sounds trivial but it takes a surprising amount of testing and bug fixing to get it right.
They finally agreed to send us the TV. Solved the issue in 10mins.
Normally I'd just use the AppleTV, but the kid stole the AppleTV to watch cartoons in the guest bedroom. I continuously surprised that a 10 year old AppleTV still a better option than using the apps that comes with the TV.
Below is what 18 seconds of web searching led me to.
https://www.reddit.com/r/PS4/comments/8u6hrm/why_does_turnin...
Bit me recently when I got a PS5 too, apparently there is a "new" thing called HDMI CEC, which for some stupid reason defaulted to "turn on TV turns on connected device" and vice-versa when first installed. I'm guessing the DR app somehow cares/sends CEC messages (not sure if that's the right terminology, but whatever) to the PS and turns it on.
Maybe forcing CEC off on both the TV and the PS can fix the issue, unless you actually use CEC for it's intended purpose.