I get what you are saying. Unfortunately not the whole of the ROG is modular, especially with specific hardware such as charging, SD card etc. Not sure how this differs compared to the steam deck.

Me too, I came from a switch, I really enjoyed it but the move for me was for the bigger variety of games and the are more specials on steam, gog etc compared to Nintendo. But bear in mind that not all games are handheld friendly.

The ROG ally is extremely easy to repair and replace parts.