I tried to do a startup in my early 30s. I'm in my late 30s now, and all I can say is having personal money and savings is HUGELY underrated. I had a LOT of stress from trying to live off a founder salary in my early 30s (AND with $8K+ of medical expenses every year), and I imagine that if I go at a startup again in my 40s it will be when I have a decent chunk of savings in the bank.