Perhaps, but most Series C equity is already paper money for employees. Companies are going to Series D/E/F rounds with regularity - and you may be looking at 5+ years to liquidity. A company that is getting tepid investor interest likely won't see a major upswing in valuation for their next round.
Consider that as you join a company working on its next round, you may have a 50% chance of major company restructuring which can range from the project you were promised vanishing, to you being laid off. A 15% chance that you get a free doubling of your equity comp on the next 409A valuation (which may be insignificant, have a 90 day exercise window, or other hijinks). While having a 35% chance that nothing major happens.
Unlike an investment portfolio, I have a finite productive lifespan where I can do good work and receive a good payoff for it. Getting stuck at a company going nowhere, or worse getting laid off from one is not a good way to spend that time.