I think maybe we're confusing terms here. Breaking up a company normally means separated into smaller existing companies. If you buy 3m's candy bar division, you still might be on the hook for the forever chemicals the candy shop dumped in the river.

If you're just talking about dissolving a company and selling off the tangible assets, not selling off functional business units then I agree, liability doesn't follow material Goods. This generally isn't considered breaking up a company.

Breaking up a large company into smaller ones during bankruptcy does not by default absolve the smaller companies of liability. Courts can add bankruptcy settlement terms that absolve a company of liability moving forward, but these can be applied to the company at all as a whole or the smaller businesses if it is broken up.