According to their site the assisted-opening knives are legal in all states, whereas switchblades aren't, so there must be some meaningful distinction (unless the law just hasn't caught up yet).
The former takes a few minutes of practice to open smoothly, the latter doesn't.
There's no reason to buy an assisted-opening knife if switchblades are also available. So yes, they absolutely exist to exploit a loophole. Loopholes in laws do tend to create (often short-lived) markets.
Having once owned a switchblade, it takes a bit of practice to hold it such a way that you can operate it but not block the path of the outswinging blade with your fingers. Watching the demonstration in this video, there doesn't seem to be any more force employed in operating the switch that there was in pressing the button. I agree that this is probably a short-lived thing that will fade away following a minor regulatory clarification.