https://en.wikipedia.org/wiki/2014_California_Proposition_47
tl;dr mostly nothing if they don't value their airbnb account.
"A person is guilty of criminal mischief in the second degree when with intent to damage property of another person, and having no right to do so nor any reasonable ground to believe that he has such right, he damages property of another person in an amount exceeding one thousand five hundred dollars.
Criminal mischief in the second degree is a class D felony."
https://www.nysenate.gov/legislation/laws/PEN/145.10
Class D non-violent felonies are worth up to seven years in prison, likely varying widely depending on the circumstances.
I guess most states probably have similar statutes on the books. Whether you could get a prosecutor to charge it probably depends on the exact circumstances. I reckon you could find cases of people being charged on much less than $1M in intentional damage, though.
Also, yea, you can commit minor crimes that don't rise to the level of extradition then skip town. That's always been the case. So? Who is going to go to the U.S., trash an AirBNB, risk getting charged with a crime and potentially banned for life from coming back? The people who trash AirBNBs are not the same people who can travel internationally, by and large.