I lived in Park City, UT throughout much of the 1990s and early 2000s. My family had a home in Telluride, so I’m familiar with the situation there, as well. I have an idea for a solution that I’m surprised was not mentioned. It’s simple: impose a heavy tax on unoccupied vacation homes but offer an exemption for owners who house one local worker on the property year-round. The concept is that the owner of a big vacation home would build a small apartment, perhaps in a basement or in the rear of the home, or even detached, that could house 1-2 locals, and would rent it out for an affordable price. In exchange, the owner gets a break from the hefty tax and they have an on-site theft deterrent.
Back in my ski town days, I had several friends who lived in peoples’ vacation homes as on-site keepers for the absentee owners. They’d keep the property secure, shovel snow if needed, stock the fridge before the owner visited, etc. In exchange, they lived there for free, or at a much-reduced rent.