Take away their licenses, they still drive. Take away their cars, they borrow one. Throw them in jail for a few years, they head for the nearest bar when they get out. They may be ill (probably are), but that doesn't mean that the public has to tolerate this. But what can be done? Not much that wouldn't be classed as cruel and unusual.
There was a post a while back that discussed the appropriateness of the death penalty for impaired driving. The argument was that the same number of people end up dead, but in this case, it's the right ones.
Want to bet that this guy pleads out and serves no more than 2 years.
Every post like this cause me to consider hanging my bike up permanently. OTOH I had more close calls when I commuted on foot.