Partly, the answer is “tough”. As a designer, you don’t and aren’t meant to have pixel-level control over the screen contents. Web is not print. Don’t ask for the PostScript standard fourteen. (Somehow this lesson comes through much better for reflowable ebooks.)
Partly, I am willing to admit that web fonts are still nice when you can get them. But they’re too unwieldy to block on (slow connections exist; font foundries are assholes[1]; etc.), and we don’t really have a solution (the problem with FOUC is not the unstyled content, it’s the layout shift).
While I'm absolutely not a design-should-rule-all person, I think there's quite a range between "pixel-level control" and "you can't choose which font to use".
If we'd reliably have the top 50 google fonts on every OS, there'd be a lot less webfonts used.
Partly, I am willing to admit that web fonts are still nice when you can get them. But they’re too unwieldy to block on (slow connections exist; font foundries are assholes[1]; etc.), and we don’t really have a solution (the problem with FOUC is not the unstyled content, it’s the layout shift).
[1] https://jakearchibald.com/2021/f1-perf-part-1/