The issue here is that a bankrupt company is breaking the contracts it made with employees — and you suggest it can be fixed by having employees enter into another contract with the same company. Do you see the problem?
What company is going to advertise months in advance that they might be going bankrupt? That's the surest way to make it come true.
This seems like some kind of weird libertarian fantasy where companies and employees have access to the same information and use it to make rational economic decisions. In reality, almost any failing company will use its payroll obligations as a bank of last resort to squeeze out that last chance of turning things around, and there's no contract that would protect employees from that.
"This seems like some kind of weird libertarian fantasy"
It's called the world we live in.
If a company's revenues are in decline, if there have been recent layoffs, well then the writing is on the wall.
A company folding should not come as a surprise to any of the employees unless the are utterly in the dark with respect to product development, revenues etc.
It's not a 'libertarian fantasy' to expect that employees etc. will have some idea of these numbers.
There's not much that can be done about solving the 'insolvency severance' deal. Severance beyond legal requirements is a bonus opportunity, and like all bonuses, it's subject to risk.
A privately held 100-person game studio doesn't share its evolving revenue numbers with creative staff. Why would the business owners do that, really?
Most private companies are strictly compartmentalized and keep production employees in the dark about the business side. Some startups do the "anyone can peek at our sales numbers and cash flows internally" thing, but that's definitely an exception even in the startup world.
I'm suggesting if people know that the company could go bankrupt, it helps them make decisions.
And that severance is a normal part of a contract otherwise