There are still plenty of ways to end up dead in the Vortex system on the open water side of the locked gate. The largest "killer" side-passage has been blocked off with rebar, but there are others.
The main, lit passage is essentially straight and plenty big, with a firehose sized hard rubber pipe running its entire length. Like Mike, I have mixed feelings about the setup. If it were mine I would definitely get rid of the lights, and I think I'd gate it about 10 yards beyond the Grim Reaper warning sign - about 65 feet deep and well before the first side tunnel that makes me really nervous.
On the "it's ok" side of the argument, hundreds of open water divers with positively horrible buoyancy and finning skills rototill their way to the gate and back month after month without incident. On the other hand, there have been several fatalities there in the past, and I just know that some day I'll get called to go in there on a recovery.
On the "third" hand, the fatalities I know of have all been off the main tunnel, poking around in places they shouldn't be, with no cave training... these people would most likely have found a way to become a diving statistic elsewhere if Vortex hadn't been handy.
Personally I don't take students back to the gate - indeed, I have all my students sign and date a statement that says "I have been briefed, and I will not go into the cave." I don't do regular Nitrox qual dives at Vortex. I do have preliminary skills training and practice there for Advanced Nitrox divers, but never in the cave.
The bottom line is, I suppose, it ain't my cave

And while I have my reservations about the setup, and I've hung up in the overhead many a time as an invisible safety valve for some folks who obviously had no business being there, I can't really make a good solid case against it.
Rick