If your RSUs vest when your company is still private, you’ll owe taxes but not be able to sell the shares for the money you’ll need to pay the taxes. That sounds way worse than options.

The most common way to issue them is so-called "double trigger" vesting where you have both a) a service requirement (the time) and b) an event required (like IPO or sale). Since you have risk of forfeiture if IPO/sale does not happen, IRS does not deem vested (and thus taxable) until both triggers are satisfied.

I didn't say it was better! I was just pointing out that "RSU, therefore liquid" can't be relied on.

Solid