Eh, I disagree. Most AAA games are still releasing on eighth gen hardware. The Steam Deck's keeping up decently well, depending on how low you're willing to drop your settings. I wouldn't want a sequel this early in the Deck's life. Besides, if you want more power, there are devices like the ROG Ally that can handle AAA with flying colors, even Starfield.
Now that I think about it-- @neku, if you're willing to pay a bit extra, you could consider a ROG Ally, or that Lenovo Legion go that's releasing soon. I think the Steam Deck offers a better user experience than the Ally thanks to its controls and software, but it might be worth considering for its more powerful hardware if you're not happy with how the Deck performs.