One of them filtered out the whole Russian alphabet, so the extension couldn't be tested by Russian-speaking users. Another one didn't allow submitting Flow posts that don't have a sufficient amount of English words from users who have less than 6 edits, so users who have a lot of edits in their home wikis, but no edits in mediawiki.org, and who want to post in languages other than English are blocked.
Wow.
I think its entirely reasonable to disable on sight any abuse filter that is that overeaching.
-- bawolff