I think for the purposes of maximum hypertrophy a good argument could be made that it's not ideal. A lot of people need 40-70 seconds of time under tension for maximum hypertrophy. Stronglift proponents will of course say a lot of that's sarcoplasmic hypertrophy, and of course they're probably right.
I think if we looked at 5x5 programs compared to traditional bodybuilding programs without dismissing the human factor (how many people actually stick to a program?) it'd score pretty high. If anybody thinks it's easy to stick to a program for maximum hypertrophy just because you know it's solid and proven to produce results I challenge you to follow some of Charles Poliquins ideas. Possibly the greatest trainer on earth but his programs can be nightmares for the typical guy in an ill-equipped gym.
He has a point though in that he often says people are delusional about how fast twitch they are. I mean, there are guys with about a 12 inch vertical and pipe cleaner arms thinking they're genetic freaks. But on the other hand he often recommends explosive concentric lifting with 4 second negatives. I don't know if most people can mentally hold up to that for very long. It gets worse too, stuff like on your last rep of chins take 30 seconds to lower yourself down. We're practically talking Heavy Duty here only with 20 times as many sets.