Sorry dude, that's not true, and is very naïve.
When you're an IC, you have no idea what your manager does. You have even less of an idea of what your manager's manager does.
I know I was naive about direct management until I tried it and realized just how much they do that I never was aware of. And as I became a more senior IC, now working directly with senior managers (managers of mangers), I found out just how much they're involved with.
At high-intensity high-output companies (including gaming ones), it's very rare that senior managers end up just resting on their laurels and letting the line managers do all the work.
First of all, it's an all-encompassing job. You are effectively oncall for various escalations, personnel issues, priority/project issues, conflicting incentives - you are responsible for all the people underneath you, and all the conflicts that might occur that direct managers don't handle - they escalate to you. At that level, there is no expectation of work-life balance, you might get called in the evening/weekend to deal with something. While you're detached from the depth, you are responsible for way more breadth.
Secondly, line managers are still expected to be primarily focused on their technical projects and their people. Senior managers have to start dealing with Legal, Marketing, Sales, Facilities, office issues, christmas party organization, press release, etc. Sure, some of it is just coordination and delegation, but the point is that you have to organize all sorts of disparate considerations that frankly are not in technical people's forte. This arguably becomes 50% or more of the job, and this is where things get really tough. Do you want someone technical for this that will be MISERABLE spending time on 50% of their job, and not doing an amazing job at it? Or do you want some MBA type that will be great, but then have no credibility with their team, no ability to influence the techncial direction, because their people will sniff out their technical weaknesses and not respect them for it.
Naturally none of this is universal. There are exceptions of exactly what you're imagining - someone that just steps back, lets everyone else do the work, and they aggregate/summarize and take all the credit. But I don't think those are actually the majority.