i assume here that you’re mostly talking about the Explore / Observation Search page (and variants of it such as My Observations). i haven’t looked at how exactly the page is structured, but based on the discussion that ends in this post (https://forum.inaturalist.org/t/observation-page-is-unavailable-in-china/36780/7), i’m guessing that it’s not a straightforward thing to redo that page to make any part of the page function without the maps being available. there had been talk in the past about revamping the Explore page (see https://forum.inaturalist.org/t/ideas-for-a-revamped-explore-observations-search-page/8439). so if that ever happens maybe that will bring with it better handling for the problem you’re describing here?
in the meantime, you may be able to filter for observations using the Identify page (https://www.inaturalist.org/observations/identify) or by using the API. (or just allow yourself access to maps.google.com.)