As a single founder, I agree. The only advice I give anyone, ever, when starting a company is to not do it alone.

Think about how much of a disadvantage you are, early on, when you have to switch between tech and business. Longer term vision vs short term. Running a product vs running a company. It's almost impossible.

That being said, you mentioned "how that would compound the difficulty involved in finding an investor." The good news is after you get a bit of success, this goes away. You can hire the things you're missing. Some things, like having a cofounder, are an early signal that goes away once things go well.

(If you ever need to talk, my email is in my bio)