Typically companies that offer RSUs have achieved scale (your Ubers and Stripes of the world), so yes the upside is lower, but the "pros" are that it's more obvious to you what the value of the grants are and you don't have any cost to exercise them like with options. These companies know that because they are less liquid vs public cos that candidates are right to discount them, which is why they usually offer more than what you'd otherwise receive from a Google or FB.
