Gregory's Server@spinal @wikipedia @kiwix They're split by language/topic & there's also nopic (no pictures) and mini (lead section only) downloads that are smaller.
I have 27 GB of zim files (wikipedia_en_all_mini, wiktionary_en_all_nopic, wikipedia_en_movies_maxi, wikipedia_en_mathematics_nopic, wikipedia_en_computer_nopic...) and I don't update them often (most recent change was adding mathematics in November).