You do need some managers. Elon Musk is trying to prove that Twitter can be run with only himself and the people who write code, and it’s not going well. It turns out that it takes a little more to run an organization than just coding and tweeting.
For example, Elon had announced that only enterprise customers who would pay $$$ would have access to the API. But he had fired everyone who was able to process an application for an enterprise license. So when the last overworked API engineer committed the change that implemented the limit, there were no paying customers because there was nobody to take the money of the few tool vendors willing to pay up.
Your overhead grows inexorably. Unless you pay very close attention, the fraction of total headcount actually writing code goes lower and lower. To avoid ending up having to take a chainsaw to your organization as Elon has done, calculate your coder percentage today and keep track of it.