> GTK4
After my comment https://news.ycombinator.com/item?id=49235430 I've investigated the high RAM jump issue a bit further. It turned out, 60 MB comes from MESA / video graphics driver, right after the first function call, that triggers OpenGL/... context initialization. Thus:
GTK2 14 MB
GTK3 24 MB
GTK4 38 MB (+ 60 MB video acceleration)
Maybe we should also ask ourselves why modern native apps need OpenGL when you used to get by with a framebuffer. You can do more things with OpenGL but are you actually doing those things?
It's almost entirely about screen resolutions. In the Turbo Pascal era the screen probably had 640x480 pixels or 307,200 pixels in total. The screen I'm looking at now is 5120x2880 = ~14.7M pixels.
If an app is maximized it has to render ~48x more pixels per frame, probably with anti-aliased text which older systems didn't use. Doing that on the CPU is not only visibly slow in many cases, but a waste of CPU time that could be better used for actual app logic. OpenGL happens to be a convenient and portable way to get the GPU to do work for you, at the cost of some memory, so GL it is.