> Everyone picking the S&P 500 over its competitors chooses that.

I'm fairly confident most people deciding to allocate to s&p trackers have no idea about rules-based vs committee-based governance. They just pick the default. And that default can quickly change if the S&P starts making weird/unpopular decisions in a highly publicized situation.

> most people deciding to allocate to s&p trackers have no idea about rules-based vs committee-based governance. They just pick the default

A lot of retail goes into S&P lookalikes. And at the end of the day, they've consistently picked one over the other.

> that default can quickly change if the S&P starts making weird/unpopular decisions in a highly publicized situation

Unlikely. Nobody has dropped NASDAQ 100-tracking funds. If anything, these guys will see long-term net inflows due to this move. S&P probably would have if they’d changed rules—this was an econometric, not business, decision.