What if it is a multi-language post? Sometimes you can see English and German for example in the same post. It also sometimes happens with KR or CN. I've seen such posts provide the information in both languages but they used the tag so people in that community knew about it.
Now being able to MUTE tags would be one way... but again it makes you blind. The communities once they are implemented will likely do the same thing without requiring you to actually be blind. You'd only see it if you subscribed to a certain community. So KR or CN might still show up in one of your communities, but odds are that if it did that it would also have english.
Communities are a feature we have been anxiously awaiting on so we can get rid of this all posts in the same inbox approach.
There are a lot of topics I am not particularly interested in. I don't want them to be invisible, but I'd prefer to only see them if I go intentionally looking.