Could you clarify your point about no downside if the company goes under? If the options are underwater then you get nothing, yet if you have RSUs, they'd be worth whatever a share of the company is worth (liquidity because of public/ private notwithstanding)
When you get options, your starting point is effectively zero because the strike price usually is zero. So if the stock goes down, you are still at zero - you just don't exercise the option. You have upside but no downside. If you have an RSU, you have the same upside and downside - 1 for 1 with the price.
Note - this isn't 100% accurate as options that are not in the money still have some value but the idea is more upside than downside.
