For the second home owners, if the assessed value tanks, their property taxes would drop. However, the tax bill would shift back to the primary home owners. The spending doesn't go away and it needs to be paid for by someone.
The funny thing about this is that it always seems to work out this way. Elected officials try to gouge someone, usually "the rich", to spend money to benefit people who want lots of services but
don't want to pay for it. And what happens? The "rich" move on, or their property value collapses, or they put off taking their capital gains, or use one of hundreds of ways, both legal and illegal, to shelter their money. Guess who gets left holding the bag? The people who didn't want to pay for it in the first place.
I would ask you, who is really greedy here, people who work hard for their money and are successful or the politicians and their supporters who covet other people's money?
If the politicians wouldn't kick off the "let's soak the rich" game and the general electorate wasn't dumb enough to expect to get something for nothing maybe we could restrain our public gluttony and control spending and everyone's taxes would be lower.