I was an L6 and, at the time, my RSUs certainly gave me pause for leaving, but in the end the urgency of my mental health won out. My timescale was dictated by getting my Green Card, not (primarily) by finances.
yeah...different story now. The target comp numbers ) assume 15% stock growth per year from when it's allocated to you. That model is now broke for the first time in a decade+. How it gets fixed... I'm not sure, but, there is history of cash payments to compensate.
Point being, if you're not making more in year 3 than year 2 -- something is broke and/or your manager wasn't supporting you appropriately, or not hitting high enough on the performance ladder.