I know what you mean, OP. Of course any sexual abuse is wrong, but I too struggle with the idea that it's 'worse' for boys and men, it's harder for them to speak about it, it's more damaging - like it's easy for girls and women to speak about it, and like it doesn't damage us.
I've often heard men who abuse children giving the excuse that they were abused in childhood themselves, which is no excuse at all - if that was the case, most abusers would be women, since more girls are abused than boys.
My take on this subject is coloured by the fact that in Ireland, 'sexual abuse' became almost synonymous with 'clerical abuse', and in most, though by no means all, of the high profile cases of priests who abused children, their victims were boys. For a long time in Ireland, the term 'Survivor of childhood sexual abuse' implied a male survivor of assault by a priest.
Since then, the range of abusers has widened - sports coaches, scout masters, teachers, doctors...still all men, of course - but the idea of the survivor being male persists.
When they come forward, men are readily believed and treated with great sympathy in the media.
The most publicised female equivalent are the survivors of institutions like the mother and child homes and the Magdalen Laundries [they were quite distinct in origin and function, but they get blurred because of obvious shared abusive characteristics].
Sexual abuse was not part of the experience in these institutions **
That leaves female survivors of childhood sexual abuse in Ireland somewhat in the shadows, whereas male survivors are emblematic.
**[I believe that is factually correct, I recall one case where a nun was imprisoned for rape of a little girl - she was claimed to have assisted the rapist; she was later completely cleared and compensated for the miscarriage of justice, but it took six years to clear her name.].