Since I'm one of the people who is on the fence about whether or not to pick up a Nintendo Switch 2 or to get myself an ROG Ally (I have $250 of gift cards for Target which don't sell the Steam Deck) so that I can play steam games on a handheld. I heartily disagree.

And it's Nintendo's anti-consumer policies that is making me hesitate on the Switch 2.

Not exactly, but overlap is significant. A bunch of people want Nintendo because they always did Nintendo and that's all they know, a bunch of people know that switch is something that kids want and so they get one, sure. But a bunch of people want to play some games lying on a couch or riding a metro or sitting in a queue at a dentist, and those people will at least google what exists on the market. This is an overlapped audience, and for a lot of them steam deck will be the obviously better choice.

They can if you install Linux on it and run a switch emu.

It's not a direct competitor, but they occupy the same niche while being a vastly superior product.

It's a comparatively new product, but it's not like it's something unsuccessful. It's attached to Steam, that everyone who ever had a computer knows about, and everyone has a couple of games there, it's being talked about very positively everywhere, and they're repeatedly gained positive reputation over pro-consumer practices they regularly employ, and they somehow evading being put on blast for the child gambling industry they operate.
They're known among gamers, which is indeed niche crowd, but also a crowd that is important here. They don't have the cultural grasp on humanity as Nintendo, or other two, but all of them shitting the bed constantly and publicly, while Valve is catching wins all over the place.