Every time I hear this I think experiences and expectations are vastly different between SV and the rest of the country. 30ish years of working in New York and I haven't encountered a single company that isn't 100% opaque about their equity to employees until time of exit/IPO. And I keep a large network.

That said, everyone here treats equity of non-public companies as if it's toilet paper. Some of my coworkers got very lucky and very rich when our company went public, but that was also a long time ago now.