It all depend on the person.
And who is attracted to a hairy or clean chest depend on the eye of the beholder.
You don't need to shave to look muscular,
however some men who have "cut" muscles like to show them off a bit more.
It's necessary for body building contests for this reason.
Some do it for swimming contests...there are a variety of reasons.
I've never found it necessary,
I've have a "decent" amount of hair on my front torso,
not too little, not too much.
And the ladies I've been with seem to appreciate it (as they play with it with their fingers
)
It's a personal choice,
if you shave it off to try it out, it will grow back quickly if you don't like it.
There's no trend, there's no good, there's no bad.
Everyone has to judge their own look and the response to it.