IC vs management, which has better job security and why?

Job security definitely IC..$s usually management..reason is that in case of layoffs people tend not to be willing to fire those who do the job and be left with management

I would say slightly more security as an IC but If you were an IC then transitioned to management in the same area due to promotions then you will have mad job security, as you will have a proven track record and know how everything works. No one will want to see you go.

Both should be same, assuming you are competent in your area

Managers are first to go in an M&A