We can remove it. If you have any alternatives people can use right now, let me know. I just have not seen anyone else implementing it yet. But maybe things are finally changing. It has been over 6 months without any movement in new search providers.
Discussion
If someone wants to use "default" relays they can use it (tab in relays settings).
No one uses the default relays. So, that's not a good assumption. In the current implementation, they can change all relays at will, but if they don't have a nip50 compliant relay in the list, the app adds one to make sure things work. Breaking seacrh-related features wouldn't be good. Again, I am happy to explore other models.