A lot of them try really hard not to. A reason for the "show desktop-version" setting's popularity. It's really sad that this has to be a thing, and doesen't really remedy the situation, more like a bandaid.

I wish Request Desktop Site would also fake a larger viewport width, maybe 1024px or so.

Without that, it’s becoming increasingly less useful IMO.

When I need fake desktop width I tend to use iCab. I suppose you could accomplish something similar with a Shortcut injecting/changing HTML using JS.