I’m not even sure it’s a man preference tbh.
But in the last 10 years, Porn has taken such a huge place. This is the only time when we all get to see naked bodies, so whatever happens in porn films has become the norm.
There is an element of ‘if you see xx happening often, it becomes normal and yummy don’t even question it anymore’ (not just for sex btw. It’s also how much men are doing in the house, racism to how we normally dress, if we snack between meals etc....)
It doesn’t mean that some people didn’t go bare before. And as a PP was saying, in the ME it’s far from being a new trend, so it will change from one culture to the next. (Eg I remember all the talk about a Brazilian when I was a teen and how strange it was for them to wax like this too)
In that way, yes it’s only a trend, fed by all the porn films.
On the other sid, because it is now seen as ‘THE norm’, there is a huge pressure for women to be bare. Pressure from friends and make partners. You just have to see comments from teenagers It’s certainly not ‘live and let live. You can do whatever you want with yur body’ but very clearly a huge pressure and shaming if you dint.