I wonder how universal these stages are. All I can say is when I worked at a 15 person company, it was extremely clear to me that we needed more structure than "everyone reports to the CEO". We struggled to prioritize between different projects, milestones weren't clearly defined or owned, at times there would be long debates on product direction without a clear decisionmaker, etc etc.

Not to say the article is so wrong. I think their advice to consider elevating a few engineers into informal tech leads is a great answer. We went with the path of hiring one dedicated "manager" of all engineers and that worked pretty well too.