Thanks to T367576: Ensure ORES topics are not loaded through legacy CommunityConfiguration code, we no longer make use of mw:MediaWiki:NewcomerTopicsOres.json. Instead, we store the topic map in the server configuration. The code change will be deployed to production with the wmf.12 train. As soon as that train is on all wikis (without any chance for a rollback), it should be possible to delete the file from MediaWiki.org safely.
This task is actionable starting January 20, 2025.