> I don't get the value from preventing a customer from modding the device.
For many, having locked down consoles is a feature not a bug. It massively reduces the odds of coming across people running cheats in online gaming. It still happens, sure. But in the end it is far less common when cheating requires buying hardware modifications from potentially shady marketplaces, soldering things on to the board, potentially breaking your hardware, and potentially blacklisting your hardware on official matchmaking systems.
You're never going to get to zero cheaters, but if you make it more difficult to cheat and make it easier to blacklist expensive hardware it'll massively reduce the odds of your player base encountering cheater in an average match. Encountering less cheaters increases player satisfaction and keeps players playing your games.
I didn't buy a game console for it to be a general purpose computer to do whatever I want, I bought a game console because I want to play games. If I want a general purpose computer to hack around with I'll go buy a Pi or an ESP32 or some other SBC instead of a Switch or an Xbox or Playstation.