actually most of the time laptops (beside super expensive macbooks) are very bad at using 4k and the screen look way blurier than a nice sony vaio 1080p screen (what an amazin computer it was) from almost 10 years ago.

especially with windows still sucking at really handling 4k

Even MacBooks are scaled to something that looks like a crisper 1440x900 (the 13-inch at least). And they aren’t 4K native resolution. It’s nice to have better looking font, but it’s the kind of feature that sort of disappears for me over a long session unless I’m comparing 2 displays.

In terms of usable screen space, 1080p can be either adequate or a little too much depending on display size. I have to zoom my X270 in a bit.

I run a 4K desktop and a 4K laptop, and both have excellent visuals with crisp text on Win10. The only things that still suck at 4K are old apps, but there's only so much the OS can do about them short of just refusing to run apps that are too old (which is the Apple way of handling such things).

If you get a screen appropriate for running at 2x zoom then there shouldn't be any visual problems caused by the rescaling.

1440 is a thing, you don't have to go right to 4k (which yeah is often going to be a mistake in a budget to mid-tier machine).