If you can find other convicted drunk drivers willing to join you AND pay the attorney's fees, court costs, expert testimony fees etc. I am sure that eventually you would find an attorney or firm willing to take the case. The bigger question is would you be successful? The answer is probably not. Your best recourse is to work on changing the law in your state. Until the law changes a class action lawsuit isn't going to be helpful. The other thing to be aware of is you more than likely will not find much support for giving a license back under any circumstances to a four time DUI offender.
"what a shame when society has the tool to stop all drunk drivers from driving drunk"
Actually most hard core DUI drivers find a way around the interlock too. All it does is slow them down. I have known more than one offender with a required interlock that gets their kids to do the blow so the car starts or another sober friend or family member. Does it stop them from driving while impaired? Nope. Not a bit.
Permanently revoking a license doesn't even keep them off the roads either. The problem with your theory that sentencing all DUI convicted offenders to an interlock is the guarantee to safety on the roads is that there are ways around it, there are your hard core drunks who are convinced they aren't impaired and continue to drive, and the ones who have no intention of stopping even if sentenced to an interlock. Not every multiple DUI offender is in recovery for their alcohol problem and sober.
Feel free to try and change the law but I don't see it happening given that states are cracking down harder on DUI not easier to keep the drunks off the road.
"That's just my opinion, then again I might be wrong." Dennis Miller