I'm certainly a fan of legislation to require severance. That said I'm also all about shaming bad actors so that other workers are aware of what they can expect when engaging them.
There is no reason to over complicate things and require businesses to directly pay, figure out how much cash to always have to be able to pay, hire auditors to make sure they have enough cash, then take them to court when they don’t have enough cash to pay, yadda yadda.
Business sells product or service. Employee sells labor to business. Government takes care of the safety nets.