If you join Uber at this point, you're only getting RSUs, not equity. They're way too large to offer shares to any more employees without triggering SEC disclosure requirements.

TBH, RSUs are better if you cannot afford to early exercise. Otherwise you have the 90 day option expiry problem after leaving your job, unlike most RSUs. Options also get bad with AMT tax if you didn't early exercise either. RSUs stay with you even after you leave the company.

Oh well, you lose long term capital gains tax benefits, but most people do not have the money to even exercise their vested options, so they sell during IPO and have equivalent tax treatment as an RSU.

Some companies now have option expiry dates at 7 years, but those can be counted on one hand.