Which country are you from? I don't see how it's physically possible to save 10 years of runway with a PhD's worth of debt and only 6 years of work. I did 10 years of labor with only a Bachelor degree's worth of university debt and my net worth is only enough to get me through 2 years if I liquidate everything... But my startup shares are illiquid (pre-ICO) and all my cryptocurrency is locked to earn forging rewards so in practice I only have about 2 months of liquid runway.