Please check EZP-18515.

If, for some reason, eZ Find is disabled and you try to index content with updatesearchindexsolr the script will try to index in solr even eZFind extension not being active.

php ezpublish/console ezpublish:legacy:script --env=dev extension/ezfind/bin/php/updatesearchindexsolr.php

In that way, it could make sense to check if eZ Find is active before indexing content.