I've gone from IC to Manager and back a couple times. The first time was becoming "manager by default" in a growing startup. I then moved on to another startup as a tech lead, became "manager by default" again, and eventually VP of Engineering. That startup was acquired and the teams dispersed, and I eventually ended up back in an IC role (which, despite assurances from my boss, ended up being a demotion resulting in lower bonus and reduced stock awards).

I sucked it up and worked as an IC for while and realized that, after 20 years, I have little interest in writing code for a living any more. I truly enjoyed the strategic and personal growth aspects of managing, so I left that company and have only taken manager roles. I find managing to be much more stressful, but supporting my people through these trying teams has been a highlight of my career.

I've done it. Like many people, I moved to the management track when my first kid was born. I realized that moving up as a manager required actually competing with the other managers and being better than them. It wasn't going to happen. As the low level project manager, I got the low level projects.

I moved back to IC when they finally posted an opening to backfill my job. I went to my boss and said: "I can be a mediocre manager or a great engineer, you choose."

Later on there was a big reshuffling of the department, and I was asked if I wanted to be a manager. I said yes. More reshuffling thinned my team down to 2 reports, and I kind of oozed my way back into IC by just doing IC work for people when I wasn't managing.

All of these moves were promotions in both pay and title.

One thing you learn by being through a few annual cycles at your business is how it really works. For instance, things like performance reviews, pay increases, promotions, etc. This knowledge will serve you in any career.

Sort of. I've worked at startups the last 10 years. I've gone from IC to "executive" three times now. Twice I decided to just join a company as an IC after leaving the last as a manager to avoid the stress/hassle and then ended up leading things. You get more insight, respect and influence on your compensation as a manager. Comp is also worse as an IC unless you get lucky or have a personal connection to the leadership.

I haven't personally, but from my experience interacting with some more traditional engineering organizations like oil and gas companies, it is incredibly common and useful there.

You have people who were managing several (5-80) engineers and technicians at a manufacturing plant, refinery, or other operational location, move to corporate and become an IC in various capacities. Some become advisors to senior mid-level, or VP-level management, or take on more commercial IC roles. They'll do those roles for a couple years and then rotate back into management in either their old orgs or the new org.