We are talking about Alienware. This won't be remotely close to 500-600$, even if sanity demands that. Which is a pity.
I don't know much about Alienware's offer (not my kind of gear), but I looked at their prices and, honestly, have no idea what you mean.
M15 laptops are in line with what I'd expect - also compared to other Dell laptops with similar components (I have no idea about Alienware's build quality).
Maybe a toned down version with a 10th gen Celeron and a smaller screen would be more closer to that. But I would put my money on Microsoft pushing ARM Windows and CFW Switch than expecting a x86 portable gaming device with a reasonable price.
So here's a starting point from Dell:
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Replace the screen for a smaller one, the keyboard for gaming controller, remove few unnecessary elements and put in the cheaper i5-1035G7.
There's easily enough space for $100+ savings and that brings us to the price range I've mentioned earlier.
Call me a kiddo (since I don't play hardcore/PC games), but I'd still pick Switch over this anyway.
The big question is: does Switch offer games you want to play?
There's a handful I'd consider (Diablo, Skyrim, Witcher, maybe some racing titles), but all of these are available on other platforms - cheaper too (Skyrim for $60?
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).
Switch exclusives aren't for me at all (it's a sea of Pokemons and some manga Final Fantasy clones).
I don't think that many mouse-and-keynoard games will be optimized well for gamepads,
Most games today are made with consoles in mind. They're perfectly fine.
Some are better with a mouse (RTS mostly), but keep in mind you're still able to use a keyboard and mouse with this handheld.
let alone the ability to run in high quality on this gaming 2-in-1, unless of course they smack in Core i9-10980HK and RTX 2080 in a body that's at least one brick thick.
That's a recipe for high-end 4K gaming, which makes little sense on such a small screen.
This concept has a 8" 1900x1200 screen.
This will be perfectly fine offering Xbox One S quality and today that's feasible with MX250 or (Vega 11, Ice Lake G7). No worries.
Switch uses a small Maxwell chip offering half of MX250 performance (at best).