Having gone through 3 business-oriented co-founders in 1 year for a b2b tech startup, in each of those inter cofounder periods where I'm the solo founder I find it extremely fruitful for product, vision, and strategy. The content, branding, business strategy, and product all much more sharply aligned.

Have become of mind it's better to go as far as you can as a solo-founder and only bring in major stakeholders when you're desperate because there's too much work.