For a 1st gen product, the Steam Deck is really well built and thought. The only issues I have with it are battery life and raw performance for latest titles. I'd even argue that disk space is ok-ish, but more is better.
This is to say, for this sort of device, raw performance is not at the top of the list. What good is to have 100FPS for 5 minutes on this type of device?
Looks like the other manufacturers specialized in these ultra portables are looking up to the Steam Deck and taking good lessons from it, plus adding their own improvements.
Regards.