I’ve worked with several excellent “just leave me alone” sysadmin types.
Perhaps I'm missing something here.
To me "individual contributor" means anyone who is NOT: A (technical) "Lead", "Chief", "Architect", or (possibly) "Staff" anything, and has no management or team-leader responsibilities.
It's not like (most) hiring managers put "not a team player" in the pro column.
For example: someone not always looking into your eyes while talking can be perceived as "rude". Same for wearing noise-canceling headphones in a talk-heavy environment. Oh, you don't drink alcohol during the "optional" Friday-afternoon company mixer? That's just weird. Want to have a day off for Eid rather than Christmas? Wellll, you did ask for it six months in advance and we did approve it already, buuuuut Dave planned a last-minute meeting which conflicts with the mandatory team meeting, so we moved the mandatory team meeting onto your day off... We'll just pay the hours you spent doing first-line support during Christmas in cash, okay?