This would presumably let x86 windows games run on ARM hardware.
This is almost certainly meant for the next Valve VR headset, but ARM has so much better power efficiency than x86 that a future ARM based Deck would be a huge improvement to battery life.
I don't think a budget deck is likely tbh. The non oled deck already goes for 250 on sales. To make a clear distinction the budget one would need to be <150. And I don't think that's feasible with all the other hardware necessary alone. Except making it a lot smaller which I don't think is a good approach.