I don't like the idea of letting him off, but he's 89 now, and it would cost a fortune for the state to pay his hospital bills as he dies. I'd say house arrest in a nursing home (at his expense) and division of his assets among his victims would be the most pragmatic solution. It would have been better for everybody if he'd died before he got behind the wheel.
House arrest would be fine....until he forgets he's under house arrest...
In most states a criminal conviction wins a civil summary judgement motion as a matter of law.
This is a Solomon moment the judge can not win. The man obviously thought he could save his car by going into the crowd where people would get out of the way. He paniced perhaps, did not think, definitly.
He may become a ward of the state anyways. He very well end up in one of those lowest end nightmare convalecent homes.
Self driving cars are hopefully going to make these events a thing of the past. (if a lexus can park itself, how soon before all cars can drive themselves.)
I would favor house arrest for the rest of his life. Not perfect, but better than probation. Did the judge bother to take away his driver's license?