All of the research being done on this is valuable, even the research that gives us the answer "Nope, that isn't it. Try again." That sort of answer lets science rule something *out*, which narrows the set of things to look at...
I can quite confidently say that this will not lead to any near-term cure. The obvious way to affect this mechanism is ACE inhibitors, and those cause birth defects. So they will have to try to a) invent a new drug based on what this tells them about the pathway to affect, b) get that drug successfully through human trials, and c) have that drug work for long enough to be worth using (48 hours, for steroid shots to take effect, is what we need right now.)
But because this is not the only thing going on in PE -- this just has to do with how to raise blood pressure, and probably doesn't affect placental abruption, or IUGR, or shallow implantation of the placenta, or liver enzymes, etc. -- it's likely that successfully targeting this pathway will slow but not stop the course of the disease.
If they can invent something from this that buys the 48 hours for steroids, that will be a *huge* advance, so I very much do hope that it is useful for that in the long run. But don't hold off on subsequent pregnancies waiting for a cure!