I did a lot of Abbyss when it just came out. It's very profitable cancer. All instanced bullshit should disappear from Eve.
It's apparently profitable for a reason, since it's objectively more dangerous than just about any other rat pack, but almost complete freedom from pvp (except the rare abyssal trace hunters) is worth it. They could seriously nerf its payoff if people figured it out but it hasn't happened yet. Overall I'd say lowsec sites have the most absurdly low value for the risk.
Being speed tanked when you're solo, or true tanked because you picked the wrong filament for your weapons, or flying out of the zone and dying because you flew into the wrong cloud near the edge, really discourages people.