Note that, with some other french speaker we’ve done a couple of experiences with language tags. Some instances ignore the c/ default language https://sh.itjust.works/post/16306134 so even if the community is properly set some languages aren’t set automatically.
Moreover some /c/ may want to be multi-lingual and then users need to set language by hand no matter what
The trick is that the fedi, has already better tools than reddit/Xitter. We can already flag the language and filter by language, which is feature reddit still doesn’t have. So it’s also about people using it rather than blocking/downvoting