>>would very much care if their holdings go up in smoke a few decades from now.

Nope

Any fund has nearly constant review of their holdings (and certainly scheduled periodic reviews), which would highlight issues with any of their holdings. Moreover, there are many hedging strategies. It isn't like companies with these kinds of externalized risks go poof in a minute. The problems, especially legal liability, become evident over the course of years, and the funds can an do adjust to not take the losses. Anything less would be a breach of their fiduciary duty to their shareholders/investors.