There are two dimensions to this: knowing stuff and act on stuff.

On one side, you have technical knowledge. At the extremes you have people who can’t even power on a laptop and expert developers in 10 languages and SREs and everything else.

Something (almost) completely orthogonal is how often you apply your technical knowledge in tasks that don’t fall into your job description. On one side you have a completely hands off manager. The other extreme is full-on micromanaging.

This basic analysis means there are at least 4 kinds of managers:

1) the non technical manager who is also completely hands off,

2) the non technical manager who always interferes with technical people’s work (maybe only based on buzzwords),

3) the technical manager who is also hands off,

4) the micro-managing technical manager.

More technical knowledge is almost always a good thing (although too much knowledge can be pointless for work purposes - if I can write ASM blindfolded but we are just writing restaurant websites, I’m not getting a real professional benefit).

More technical action is not always an advantage, to you (more work) and to others (micromanaging).

The reason this works with startups at an early stage is, simply, that few tasks are outside the manager’s job description, since they are essentially founders+marketing+finance+everything else. However, when you have to scale, you need to act less from a technical standpoint even if your knowledge is useful to understand stuff.

Being familiar with tech is important, but being a 'tech head' is not. A CEO needs to be familiar with the product, marketing, sales, HR, and all the other parts of a company. If you are highly focused on one aspect, it can be disastrous for the business. Your job is to get the right people in the right positions and use their knowledge to make the right decisions. A CEO's superpower is making the right choice with the information available, which means you must get the right information from your staff. I can see a tech head being very important at a technology-based startup. However, once you have a product you can sell to investors or users, you need to let go and determine how to survive and thrive as a company. Tech is just one more thing you need to know as a CEO, but it is by no means the most important.