If you hit someone hard enough to break their board, one or both people are not going to walk away from that accident. If a broken board was the only carnage after hitting someone that hard I'd consider myself lucky.
Splitting the cost of a new board seems reasonable, but not necessary. Any board on the snow has been used. Just because someone jacked my board up doesn't entitle me to a glossy new board.
How do you ask someone to pay for a $2500 virus they just broke? How do you put a value on a NOS board that's not made anymore?
When you take you gear to the hill you assume the risk that it might not make it home in one piece. Materials could fail, you could hit a tree, you could hit a landing wrong, you could stuff the nose hard.
What if you do any of these to avoid someone who is out of control, and subsequently break your own equipment? Should they pay because they were out of control even if they didnt hit you physically?
Big bag of worms for sure.