A typical acquisition of the legal entity from the shareholders provides protection because there’s no limited liability in the deal (as it’s a sale by the shareholders (as individuals)). An asset sale has higher risk for the buyer (because the sale is, essentially, looting the corpse of a legal entity) with the benefit of not having any liability for the legal entity’s past deeds. Purchasing assets from the company while also expecting the former owner to be on the hook for the value of assets is trying to eat their cake and keep you on the hook to make them another cake.
That said, U.S. LLCs are not normal limited liability companies (like they are in the rest of the world). A U.S. LLC is a weird amalgamation of tax and law. Perhaps what you’re describing (as described to you buy your lawyer) is just one more weird aspect of U.S. LLCs.
(Outside of the U.S., a limited liability company is nothing like a U.S. LLC. The closest the U.S. has to a typical limited liability company is an Inc.)
What are named something like “limited liability company” in other countries are, as GP said, not equivalent to LLCs, they are approximately the same thing as US corporations.
US LLCs are a comparatively newer business form that was created mainly to be a streamlined form (compared to a corporation) for corporate joint ventures. They've since become popular for other uses beyond the original focus.
That said, U.S. LLCs are not normal limited liability companies (like they are in the rest of the world). A U.S. LLC is a weird amalgamation of tax and law. Perhaps what you’re describing (as described to you buy your lawyer) is just one more weird aspect of U.S. LLCs.
(Outside of the U.S., a limited liability company is nothing like a U.S. LLC. The closest the U.S. has to a typical limited liability company is an Inc.)