the goal of limited liability is not specifically to help startups, it's a common law concept that predates "startups" by hundreds of years. I would argue that it helps the little guy much more than the extremely wealthy. I personally could not invest at all if I couldn't limit my losses to the amount of money I put in. people with millions of dollars can take on a lot more risk without becoming homeless if one or two holdings goes belly-up.
Part of the difficulty here is that ownership confers some power to shareholders (the ability to vote in some corporate matters) but doesn't confer any responsibility for those decisions. For the average investor, this is a good thing: I don't have time to vote in every shareholder election I hold the right to vote in, so it doesn't make sense to hold me liable for elections I didn't vote in.
A possible solution here is non-voting shares. Limited liability could easily apply only to those holding non-voting shares, and people could have the ability to convert voting shares into non-voting shares if they don't intend to vote in shareholder elections.
If the goal is specifically to assist startups, then let's find some way to codify that. It sounds like one of those cases of unintended consequences. Is it trying to help out the little guy? It sure looks like it's helping the rich stay rich.