13 states use true comparative negligence, so it's not just California. Another 33 states use a modified comparative negligence which bars recovery if the plaintiff is 50% (or 51%, depending on the state) or more at fault.
I agree it can be a great training tool. They just need to tweak some things to protect the general public.
The change in the TOS should protect them from suits by users (or their families), but it won't protect them from suits by injured/killed bystanders (like the old man's family in SF).