[Latty]

I mean, you say that, but on KDE, for example, every application except one on my system works with DPI scaling (the odd one out is Unity3D) - that's because at the QT level DPI scaling is built-in, so the toolkit supports it and the applications get it for free. Clearly this wasn't the case for the older Windows UI stuff, where they are literally just scaling the image of the window up (which means horrible looking text).

[vetinari]

Actually, the really old windows stuff did support scaling - the 'Large fonts (120%)' option was there almost forever. I remember that original Delphi, circa 1995, supported it.

Just most apps chose to ignore it, the developers took the 'anyone uses 96 dpi anyway' attitude and at the end of 90's most applications started to suck at 120 dpi.

[pjmlp]

Yep, Windows API already had support for logical pixels in the 16 bit days and all good books always preached to convert between logical pixels and physical ones.

I guess people got lazy, as you say.

[kpil]

I think that the monitors stayed more or less the same later pixel density for a very long time. Is only been gradually increasing very slowly for 20 years, until a few years ago.

No point in spending time on logical pixels if it makes almost no relevant difference...

It's

[freeone3000]

Anything running its own renderer doesn't get to benefit from component scaling since they don't use components.

[Latty]

That was my point - running KDE, this is extremely uncommon, running Windows, it's practically every application.