There are many things that a person can do to liberate their time so they have the flexibility to spend good chunks of flexible time on their startup. Those things (e.g. moving to a more consulting/self-employed type role, not an employee role) also teach that person how to run a profitable business, deal with taxes, cash flow, sales, etc. Having someone else's money in your bank account teaches none of that.
I agree that it is far better to be in a position to work full-time on your startup, but I think it is not so valuable that it is worth taking the downside of raising funds just for that. "Relentlessly resourceful" (to use pg's words) people find the time to make it happen somehow.
Similarly, relentlessly resourceful people make it happen without having to fly to east bumfuck. Shit, in today's world, with all the remote communications available, and the fact that most companies (at least the SMEs) are perfectly happy to do business remotely. And if your business requires you to go to east bumfuck to make sales in person, and you don't have the resources to do so, then you're just doing the wrong business. Pivot to one where you can do the sales remotely, or there are enough clients nearby to sell to.