I don't expect level 4+ autonomous vehicles any time soon, but the "trolley problem" is an irrelevant distraction. It's not something that comes up in real world collisions. There's never an even choice between hitting one of two targets. Other factors are always present and dictate the safest course of action.

The Trolley Problem is only a problem in theory. In real life no one but the victim of a psychopath who has carefully stage managed the problem ever has to confront it.

When one in real life has such a problem one doesn't have time for reflection, adrenalin and social conditioning take over.

People jump in front of trains to rescue other people careless of the harm that might be done to their families and friend should they die in the attempt.

Moral and ethical dilemmas, unfortunately (in my view as someone very sympathetic to philosophical investigation) seem only rarely to deter the inventors of technology and even more rarely deter the companies who employ these inventors and engineers.

The trolley problem is not relevant because an autonomous vehicle should never put itself in a position where it might drive into anything.

We already have the trolley problem with human drivers, yet humans are allowed to drive cars.