For options, taxes only become a big limiter if one waited for the value to rise substantially from the strike price, thus creating a large spread that will be taxed as income. If shares are purchased as they vest and held for over a year, the gains will be subject to much more favorable long term tax treatment when sold.

Larger companies will typically switch to RSUs, which get taxed like income, and isn't great for a non-liquid asset. Thats what double-trigger RSUs solve, by not having the employee own the shares until a liquidity event, they won't need to pay taxes on them until it happens. The catch is that now the employee needs to hold onto the shares for a year to get a more favorable tax treatment.

Taxes will really only take close to half if employees insist on selling their shares in less than a year.