Lately I’ve been trying to use mojeek, which (to my understanding) unlike other sites like DDG actually has its own crawler whereas most alternatives are just frontends for google/bing.

This is correct, there aren’t many, and we recently passed 7.7bn pages. You can actually help with any wonkyness through feedback, but also we have this page which we trial new algos on; there’s a large update sat on it currently.