it's about a number of safety properties always holding as long as the assumptions are true
And no project is ever without such assumptions. You can't have abstractions without them.
And no project is ever without such assumptions. You can't have abstractions without them.
Some may argue that there's no guarantee that such proofs apply to real world systems. But really, there's no guarantee that any abstract model does. We humans have to get paid for something.
I would argue that those who would argue that have probably not spent a lot of time doing any real-world formal verification.
People seem to like arguing about its utility in the abstract without ever doing it.
In short: most of the objections people have to formal verification also apply to modeling something in software to begin with.