Those have only really caught on more recently.

And as more and more investment moves into them, they become mono-cultures vulnerable to large-scale exploitation.

I'm using some right now, but I don't count on their indefinite viability and performance.

Remember how LIBOR exposed fundamental problems and manipulation with respect to indexing and pricing?

Different aspect of finance. Nonetheless, you're pinning everything to indexes someone manages -- and to systems performance versus competition.

They do reflect a similar aspect; taking the average investor's attention away from individual purchases and sales, where most get fleeced to varying degrees.

Wherever your investments, you have to keep paying attention.

P.S. Have an upvote. I'm not disagreeing.

I agree that there is concern for large scale manipulation, but it seems like that concern is still there with actively managed investments. Especially from governments manipulating via bailouts. At least with passive index, you're only paying a few basis points.