Startup employees get fraction of a percent of ownership whilst taking relatively similar risk profiles - as in pennies on the dollar and last I checked pennies are pretty worthless. Hence the heuristic. Yes - you need a bunch of equity to make it worth it - my point with that heuristic was that employees don't usually get a meaningful enough amount of stock. Furthermore - due to the various stock class structures - the stock may also be diluted away upon exit or subsequent investment rounds.
