Are girls with thick eyebrows attractive?

Why wouldn't they be? Men find various traits in women to be attractive. What's attractive to one man won't be attractive to another.

It all depends on what you like. In my opinion, no.

That's right. Girls with thick eyebrows are impressive and attractive.

Women with thick eyebrows can be considered just as attractive as those with thinner eyebrows.  There are, however, exceptions to this rule.  Certain eyebrow styles simply don't suit everyone, and I'll explain why below.

As with all aspects of the body, people have a variety of different shaped and sized eyebrows.  If left to grow naturally, eyebrows will tend to follow the bone structure of the face.

If you have a prominent facial structure, therefore, your face is naturally more suited to thicker eyebrows.  Likewise, if you have delicate facial features, your face is more suited to thinner eyebrows.

Personal taste

There is room for personal taste when it comes to eyebrow thickness, but people may be deemed more attractive if their choice of eyebrow thickness matches their facial structure.

Thick eyebrows are likely to look a little odd on the face of someone with very subtle facial features.  Again, thin eyebrows will look very strange on someone with a strong facial structure.

The best thing a woman can do, in my opinion, is to allow their eyebrows to follow their facial features, and simply tidy them up with tweezers.  That way, you're less likely to have eyebrows that are considered unattractive.