Is the desktop environment relevant? I thought MC (re)implemented all of this functionality itself so was largely decoupled from the underlying environment. This is just an assumption though so not sure if it is really true.
The desktop environment doesn't affect MC directly; I'm saying that for many Linux users scaling must be set in two places as an ordinary matter, so the fact that MC requires one to set scaling in two places wouldn't be unfamiliar or different, whereas windows users expect to set the scaling one place and have everything sorted. It was more a comment about likely user expectations than about how the DE interacts with MC, if that makes sense.
Anyway I can only comment on this device, on Windows it looks fine out of the box so I haven't had to tweak at all whereas on Linux it looks bad. The font and window scaling looks a bit odd on Linux as the spacing seems off to me, if it looks worse and/or is more fiddly on Windows then that seems like a somewhat pyrrhic victory to me
Oh I don't think it's a victory exactly; it would be better if one could change only one setting and have it work, and better yet if it could get automagically detect the resolution or get the scale factor(s) from the DE's environment variables and scale automatically rather than requiring the user to manually set it. My comment was more of a negative comment about how weirdly the windows font settings work when you're using scaling, the absence of which is a beneficial side effect of the Linux setting separation.
In re: spacing, have you verified that you're using the same fonts on Linux and Windows? I don't think Linux ships the windows default font that MC uses (you need to install the proprietary windows fonts separately), and it may be that they would look more similar with the same font.