They would have to be rubber domes. They just have that obvious non-mechanical look to them, and they were both made during the time where mechanical keyboards were being phased out for rubber dome keyboards.
The conclusion is bollocks. I just got a couple of boxes full of "mechanical" keyboards from that time, with various similar layouts; some have Windows keys, some don't—it's a lottery. That said, these mechanical-contact switches are mostly cheap clones and not worth the time generally. Stuff like APC Clicker, Aristotles and Taiwan * switches, clones of simplified Alps, Acer switches… One of the notable few exceptions being Chicony KB-5981 w/ Monterey switches. I tend to keep them only to harvest keycaps (if they're Alps/MX compatible).
That said, the OP's chicony has an unique layout: the large modifiers are specific to this product series (5911, 2923 and similar). That's a rubber dome over membrane for sure.
But I'd have to disagree with your view on Samsung rubber domes. IMO they're some of the best (pure) rubber domes I've ever tried, I like them even more than BTC and NMB dome with sliders.
Either Samsung supplied various keyboards to different markets, or we have incompatible ideas about what's "good".
Those were (and still are) common in libraries, where I live, and I remember we had them in the home office in early 2000s. I didn't mind it back then (which is weird, because I was coming from objectively much better keyboards), but now when I stumble upon one, it's always horrendous: stiff, almost linear and extremely gritty. Sort of like dirty Cherry MY. (And I actually don't mind MY in good condition all that much.)
