I am waiting for someone at Apple[1] to explain why I can't set any arbitrary site as my search provider on mobile on the phone that I paid for.
(Does Chrome on mobile allow it? I use Edge on iOS which also only has a hardcoded list, so while I don't know for sure, but I assume not)
[1] no doubt i will be waiting until i am dead
I'm guessing that apple wants to get paid for placement in the preferred search provider listing.