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I don't think docked will be a problem for the vast majority of third party, at least while they are supporting Series S anyway.
But undocked is going to be interesting to see how performance is on games that are only on "next-gen" consoles.
Games like Alan Wake 2 that run at 720p30 on the Series S, If the Switch 2 is significantly less powerful handheld than docked, like the Switch 1 was and the leaked clock speeds say, then that could be a problem.
I think Star Wars Outlaws is the only AAA next-gen port announced at the moment so how that runs on a Switch 2 handheld and what kind of sacrifices they need to make will be very interesting to see as that's also a difficult game to run. Regularly below 1080p30 on Series S and not really playable on a Steam Deck.
