They're just poster children for the particular brand of disdain $100k+/year "tech workers" bear for their users: they make enough for the shiniest of toys, so they're too far above spending their valuable time to make their software run smooth on our $100 crap phones. Nevermind that each Fb client update likely produces hundreds of tons of toxic trash called gadgets. Sure, sometimes they do optimizations. Generally, though, both Fb and Google keep exploring the physical limits to code bloat. Remember that one time that Fb hit the JVM class count limit?

FAANG are the worst offenders. Didn't facebook employ ungodly hacks to unload/load parts of the android app to navigate around the 65k method limit of dex? Have you looked at the js monstrosity of the Google hardware shop website?

I wasn't speaking of a 4k TV, but still, this doesn't check out. A single 2160p framebuffer is 8MPix, or 32MiB. Not counting the original FB size, the extra 1.5GiB are enough for 48 whole framebuffers. You don't need that much image data all at once, the number is ridiculous. No, I believe it's just that the code became that much less efficient.