In which case you would get people with different views of what's going on - some people could see some articles but not others. Confusion would then be a problem - it's one we already have on forums that allow editing or deletion of commentary.
This is a pretty common argument, I see it a lot when someone suggests forums should let people delete posts. There's always someone saying it makes the forum impossible to read.
Well, if there's one thing we know from 10 years of reddit its that people being able to delete content and usernames completely has negligible impact on readability.
Similarly, with 20 years of experience with ignore lists, I can confidently say that what small amounts of confusion might occasionally be generated from my ignore list being different to yours are well offset by the benefits of us being able to choose who we don't want to interact with.
