You may reasonably asssume that Twitter does and does not. Twitter will try to group users into audiences, probably in ways no human really understands even if

You may reasonably asssume that Twitter does and does not. Twitter will try to group users into audiences, probably in ways no human really understands even if some humans know enough to read the log files and databases. Do you read Czech tweets? You probably understand that language, then, so you're added to the appropriate bucket of users. Do you retweet things later that go viral? Do you retweet things that are later deleted by moderators? Another company that did something very like this for recommendation purposes ended up with considerably more than 1000 audiences, and the nazis were concentrated into fewer than 100 of those, even though separating nazis from the rest wasn't a goal. Not perfectly concentrated.