Wats, I think the crime in this case was mainly the self confessed grooming. It wasn't an opportunist, spur of the moment snog and a grope in a nightclub. It was a campaign over a period of time by a privileged man in his late twenties to manipulate a 15 year old into having sex with him. The fact that it seems he failed is irrelevant. In that sense it was certainly a psychological attack. He asked her to delete their electronic conversations, he tried to cover his tracks. This was a calculated plan to exploit someone who was clearly gullible and vulnerable.Well I didn't say the third thing for a start.
It was consensual- she consented to it. That doesn't make it ok but it would wrong to label this a sex 'attack'. I don't know how much simpler that statement needs to be.
Most 15-year-olds are "at it" if by "at it" you mean taking part in sexual acts. Most are having full sex by 16-17 so it would be both wrong and naive to think they aren't doing other things at 15 and often younger and often with those the other side of the age of consent which happens to be 16.
None of that makes me an apologist and I dislike the accusation. I'm just trying to give a point of view a bit more considered than "hang the nonce" or "what if it was your daughter".
I have no idea how long he should get, and don't really care, but this certainly isn't anything like two teenagers a year or two apart in age having a grapple.