The issue is that if it becomes a government fund the insurers can't spend the money in the year when we didn't have destructive hurricanes, which is what they usually do.
The government would keep the money in the fund indefinitely until it was needed and would't be spending it.
That is not something that's happening; surplus is tightly regulated now in Florida. Plus, reinsurers will not let insurers steal money that's meant to cover losses. It's cheaper for Florida to tweak the dials of surplus regulation than to become an insurance company because it would encourage loss-making behavior.
The government would keep the money in the fund indefinitely until it was needed and would't be spending it.