You don't need to be an great engineer to be a good manager, but it definitely helps when your manager knows enough about the battles fought in the trenches and can offer actual feedback/support instead of nodding for 30m, then going to another 1:1.
There's no magic to it but, sadly, that combination of qualities is a lot less common than I would like.
As a little anecdote, my first boss was a technical manager with many years of experience in programming but unfortunately not very good managerial skills. The biggest problem was that he had a clear image of the big picture but when we try to explain to him that "No, we can't do X because Y" then he said, "what are you talking about? Of course, we can It's a simple queue/query/function call", and he would not listen until we show and explain him the code or he tried to do it himself.
It's definitely better to have an empathic and cooperative manager even if he or she lags the technical knowledge
It's rare to find a company balanced in the middle where they're looking for someone who clearly "gets it" and can talk about technical solutions, but also has the ability to solve the people problems. (Often good managers were also skilled ICs before they made the jump, but lack of everyday practical use leaves them with a layer of rust. In an hour interview with someone you've never met before it's hard to tell the difference between "rust" and "has heard of the concepts but doesn't really understand them" though)
Obviously there's a spectrum of management that an IC can undertaken, but this is typically based around their good will and soft powers, but the wider point is they're not supported to have direct reports.
The idea is to genuinely belong to a team, not just on an org chart. When troops are in the battle field, they form unbreakable bonds because they have trust, got each other's backs and there is absolutely nothing artificial about it - life is on the line. More often than not, I've seen managers appear genuine but are not internally so and it will surface in future if not now.
Also, corporations, midsized companies and even small companies have this idea of not speaking the mind. Instead, massive amounts of bullshit corp speak and lipstick is put on the pig to do a quick dog and pony show for the upper management. Managers that suck up to upper management lose their support from the troops. Once that's done, there is no going back.
One downside of relevant coding experience is that the EM will get involved in more and more little technical details, which bleeds into micromanagement territory.
It's a bit grating to be told that "you're the expert, I expect you to decide these things" and then have every detail nitpicked over and argued with anyway.