One potential case for extending (or providing an alternative implementation of such aggregator) is such where you would have a certain logic to automatically select a provider based on your query. For example -> use geoip2 for valid IP address geocode() calls, use google maps for anything else. Given the popularity of the library, I think more options to extend the library are better.
From https://github.com/geocoder-php/Geocoder/issues/727#issuecomment-312446873
Ping @ddinchev