I am 36 years old and have founded 2 companies. One with a co-founder and the other I gave near-founder equity after 2 years. Both relationships ended poorly.

They say finding a co-founder is akin to finding a spouse. In this country > 50% of marriages fail, what does that tell you?

I believe that for those adequately capitalized they should fund themselves and then hire for skill-set gaps. If you need the financial and technical resources of 2 or more then just be careful what you wish for and take off the rose colored glasses before entering the relationship.

Lastly I would offer that a multi-person team needs a clear and elected leader (CEO), there are far too many decisions in building a company to expect that a democracy can compete.

The above is offered as testament to real-life experience. There are obviously going to be exceptions that have worked out great...and I'm happy for you!