The mediocre ratings and mixed feelings given by most users is a good reflection of the state of most modern anime...trash. Tomo-chan wa Onnanoko is a breathe of fresh air to the stale romance genre. As someone who has read the manga, this anime is a very good adaptation with good standard artstyle and great voice acting. More than anything, it is hilarious and I find myself laughing out loud several times (not just blowing air through my nose).
I think anyone who dislikes the general and boring cliche of romance anime will enjoy this interesting spin. This show is for men of culture.
Note: I personally have recently struggled watching anime due to slow and boring paces, and predictable and repetitive tropes. I usually drop trash anime quite easily. Even watching enjoyable shows can be difficult. This is not the case with this one - it's great.
edit1: also the op is great