But, why care? (Yes, we can “care” that there was a leak - but… why worry? what new risk exists today that didn’t yesterday?)

The data in the leak (other than follower count, etc) was already available for purchase from Zoominfo, 8sense, or a variety of other data brokers or other legal marketplaces for PII.

I suppose the risk now is that the data is freely available and no longer behind a data broker’s paywall?