I’m at a FAANG in a senior role. I certainly write less code now than when I wasn’t in a senior role. They pay me more for my experience and ability to technically lead my team without being afraid of ambiguity. A big part of that is being a force multiplier and growing the more junior folks.
Writing is a strong skill - being able to articulate your ideas, whether in a design doc or other communication is critical. Clearly explaining pros and cons and whatever alternatives you considered - I wouldn’t discount any of this work.
I was at one point on a team where I didn’t feel like the technical side was sufficient (for me), and so I left that team.
I wouldn’t let my ability to quickly grasp some code base on github be a personal test for whether my skills are rusty or not rusty. That sounds impulsive to me (no offense but I would react this way earlier on in my career).
Try to tease apart specifically what it is you’re missing - do you not feel fulfilled? Is there a certain kind of technical challenge you want? Is there a specific problem domain you want to work on? I’d start with that to figure out what it is you want to do.