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.
I think this is good advice only if you know someone who would be perfect as cofounder who you have a long working relationship with.
Otherwise "get a cofounder to get a cofounder" can definitely ruin a project. Am someone who went through 3 in one year, made it harder to change things, strategize, and there was always some misalignment between product, sales, and content. Find that I'm making significantly more progress as solo founder now.
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)