Unfortunately you are wrong. Everything we call tech is in fact driven by fashion.
My older version Mac is badgering me to upgrade to Bug Sur. Top feature: 100 new emojis. That is what Apple prioritised. Why the hell are emojis even part of the OS let alone its top feature!
Truth is GUIs are done, were a decade or more ago. All there is left now is change for the sake of change. And Apple can’t think of anything more to do in the real OS either!
UIs are definitely fashion. We're going round and round in circles and things aren't getting better, IMHO.
Rendering a font, and a font, are two different things no? It should need an OS update to add some more characters.
I’m saying this like an old man (even though I’m not even close), but we’ve seen it before and we’ll see it again.
It is a cheap and immediately gratifying feature whereas users might not care about or understand the more substantive parts of an update.
Because Apple controls the end devices an OS update is very simple and goes out to basically all users so they don't have to rely on weird slide loading hacks that are typical for platforms like Android.