There is a huge difference between stock price being 20% lower than RSU grant price vs. 20% below option strike price. With options. If options are way out of the money, then they're worth a lot less than the RSUs.

Far from being pedantic: having underwater on options is very different from having RSUs worth less than they were in the past. If an individual were to liquidate one of each; the underwater option would have negative monetary value, whereas the RSUs will always have a positive value.

Never mind the convoluted tax implications of exercising options that are nominally not underwater, but whose stock has a lower value that at the time of granting.