Techblogger basically nailed it. Looking at the comment and the others by that account it wasn't at all clear that was a real person. Lots and lots of one or two sentence comments not really saying much, very seldom upvoted, and no original posts from that account. It wouldn't really have mattered if it was perfect English to me, I would still have downvoted.
Since you have taken the time to vouch for your friend and asked nicely I have removed my downvote. My advice to your friend is don't feel the need to post so many comments like that - a simple upvote is sufficient. If you have something that ads to the conversation - asks new questions or brings new information that is the time to post. Don't worry about the language - if necessary write in your own and post a link to Google translate, it is actually very good for most languages these days. Or post a translated version and then your native original. I do know how frustrating it is when you are a minnow and facing an exponential battle to increase your reputation. Just keep at it - post your own original content, add comments that add to the conversation, write about what you know about and follow others similarly interested and you'll be soon growing in reputation and influence. Good luck!