@Douglas353 That is some seriously tortured logic.
There are indeed some legislative reasons that the US has such an extreme number of mass shootings and other gun crimes compared to other countries, but could you please put your thinking cap on for a minute and consider what the key variable might be?
If your answer is "Airbnb," I have a feeling you're not going to be our next Jeopardy champion.
Nobody can possibly know what other counterfactuals might have averted the Orinda shooting, but you're down a strange path there. The US has had mass shootings in schools, malls, churches, a post office, a Wal-Mart, and every other type of place where multiple people in shooting range can be found. One remark I've never heard from the peanut gallery is "let's ban schools, malls, and churches because they decrease the overall quality of our communities, as evidenced by the mass shooters they attract."
As it were, your community's horrible event happened at a house party that got way out of hand. Fun fact : those used to happen in the suburbs all the time before Airbnb came along. Haven't you ever seen a teen movie from the 80s?