Both approaches can work, but lead to different outcomes. The market for "todo list" apps is absolutely big enough there's room for more than one company.
The beauty of the bootstrapped model is you don't need to "win the market" or "beat the competition". Is it making a profit? Congratulations! You're now the owner successful company. Want to grow the company? Re-invest the profits, not your personal life savings.
If the goal is to "win"... ya, you're probably going to need to spend money like it's someone else's, and should take that VC money.
If the goal is to "win"... ya, you're probably going to need to spend money like it's someone else's, and should take that VC money.