Did most of the web suck when we were on 28k or 56k modems? I'd argue that it didn't, and yet even with the light weight of pages back then, it was incredibly slower than today's pages (even heavy ones) load over our much-faster connections.

So really, I think what the author is observing is that having experienced high-speed reliable connections, it is very disappointing to move to a much slower connection. For the emerging tech markets, I can imagine the experience would not be great if the load was long enough to cause timeouts and connection failures, but at the same time, the 99% experience, as it probably was when the web was born, is "holy crap look at everything I have access to now!"

Yes, there are some really terribly optimized and redirect-happy sites out there and yes, you should do everything you can to make your page speedy. Everybody benefits when you do. I think, though, that this is more of a case of "let's be thankful for and aware of what we have," and "if you suddenly have a slower connection you might find yourself annoyed" more than "most sites suck on slow connections."