Such companies will have a career ladder up to Principal or Distinguished engineer. You will have to share your knowledge, of course, but without having to give up coding and do people management, if you don't want that.
I'm 39, happy infrastructure engineer, individual contributor. I tried being team lead for some years, but didn't really enjoy people management. That's okay.
Charity Majors wrote some great posts about that:
- https://charity.wtf/2019/09/08/reasons-not-to-be-a-manager/
- https://charity.wtf/2019/11/23/questionable-advice-after-bei...
- https://charity.wtf/2020/09/01/the-official-authorized-list-...
- https://charity.wtf/2020/09/06/if-management-isnt-a-promotio...