I went through just about every family of PDA and smartphone before the iPhone came out. Their web browsing universally sucked. The iPhone was a huge leap beyond other mobile browsers. The whole idea of clicking links being agonizing is either fiction or hyperbole.
It's funny you claim YouTube and Facebook would be terrible on EDGE when both services had mobile apps in the days of EDGE, YouTube even shipped on the iPhone. That isn't to say they aren't better served by higher bandwidth cellular service but they existed and functioned in the past.
High bandwidth connections are expected today and plenty of services would be unworkable without them. At the same time many web services are downright wasteful in their design and implementation.
Increased end-user bandwidth has just been eaten up by lazier or stupider designs and implementations. I fully expect these trends to continue as 5G rolls out. No one will actually do anything interesting because sites will load twice the ads (in 4K) and quadruple the size of their JavaScript bundles.
>clicking links being agonizing is either fiction or hyperbole.
Web 1.0 over EDGE is agonizing in latency. Without Javascript, every action that isn't a #anchor in the same page becomes a round trip. If your radio has gone to sleep, it takes even longer. And I was being charitable giving you EDGE, in 2007, many people were still on GPRS.
It's absolutely self evident that faster networks enable entirely new applications, just like increased memory beyond the 640k limit enabled new apps.
I used to joke that slapping Gopher or a libcurses based apps on these phones would be superior (IMHO, the experience was inferior to an Amiga on a v34 modem dial to Unix)
Mobile Web apps are not really functional at EDGE speeds. And certainly todays' media, which is rich with imagery, would be completely overwhelmed at EDGE/3g speeds, even if you remove the overhead of HTML and JS bundles.
Facebook, YouTube, Spotify, all of these apps would be terrible on EDGE.
The thing is, we are so used to high bandwidth now and its availability, we seldom realize how dependent we are on it until we lose it.