Do women in their late 40’s find really young men attractive, and even if they would never sleep with one so young, how many still fantasies about it, and flirt?
Any man or woman who is honest about their sexuality will admit that they will find people of various ages attractive. That doesn't mean that we will always go out and have sex with everybody or anybody that we find attractive.
Particularly if we know what is legal and illegal.
Much of what you're talking about is a construct of porn, this particular subject. I barely legal young man and a middle-aged woman is usually one fabricated by a young man who is misled by porn.
Are there who would of course there are. You will always find somebody who will do things that others will not.
Personally I would never have sex with somebody so young, no matter how attractive they find them.
My husband agrees there are limits that we need to abide by.