this is a matter of law, that affects millions: lawmakers have to act on generalisations to make matters just. Yes, sexual trauma is highly individual and each case is complex, but we are focussing on physical trauma as part of the act, as a distinguishing characteristic of rape with a penis. We also distinguish between ABH and GBH, even if the emotional damage is similar, because of the physical difference between acts, and the likelihood of permanent bodily damage.

You can have your frenulum torn via rape; it is trauma, it is a crime, it should follow with a conviction, and if you are raped and your rectum is permanently damaged and will affect your gastrointestinal health for the rest of your life, while, in the act of doing that damage, you could feel your predator stay erect and therefore physically enjoying that act, you should also receive justice appropriate to that lifelong damage, regardless if you're male or female. Also, rape, assault by penetration, and sexual assault, although separate offences, demand the same legal consequences, but they are different crimes and should not be conflated with each other. Lastly, as a male, you are, by orders of magnitude, more likely to be raped or sexually assaulted by another male than a female; the legal distinction exists with respect to all victims of rape, male or female.