I think the internet really exacerbates the problem though. It's one thing if PowerPoint animations don't work well on an old computer, but with network requests it's like people don't even realize that something that happens quickly on localhost will hit a lot more latency in the real world.
I like this explanation (somewhat down the page) of why Twitter changed in 2012 from a single-page app to more server-side rendering. http://tomdale.net/2015/02/youre-missing-the-point-of-server...
It can also be a problem in business apps where developers don't consider the restrictions on a network.
I have regularly seen apps link to third party social network libraries synchronously. The problem is that corporations will routinely block things like Twitter. You have to wait for the connection to timeout because the domain is blocked.
Also http connections are often closed prematurely by proxies and firewalls and can take seconds to restablish. Apps will often lack sufficiently robust keep-alive so the user will suddenly have an unreposive site.
It's a problem that's been around forever. I dunno how we solve it, but I applaud Facebook for at least trying.