API: /search, why is parameter "query" required?

I have reviewed a previous post from 2017:

Understanding the Search API query parameter

It is still not clear to me why parameter "query" required when there are other parameters may be sufficient for searching for one or more items.

If a /search request is for items of type folder within a specific ancestor_folder_ids, then the parameter query would not be needed.

If the parameter query is required, then provide a wildcard "*" to allow any value.