Yes. But I’d caution to not conflating passive investing with indexing to a popular index. They sound similar. But most passive assets index to one of a variety of indices, many of them built in-house by various asset managers. (Vanguard, for example, is famous for doing this.)
Yes.
And just because yesterday's rules were "invest in S&P500" does not mean the governors of many (not all) funds cannot change the rules to dodge such blatant fraud
The managers of huge funds are not complete idiots- far from it- and they will do what they can, most of them, to fulfill their duties