Boys will be boys. This is not an opinion. This is a very simple fact. Boys may become many things indeed but the fact remains that at whatever point they are or have been boys. Saying or not saying these words will never change anything about this again very simple fact.
What is a toxin? In medicine a 'disease' or sickness is defined as a cause that interrupts the normal functioning of cells within the body. A 'symptom' is recognised as the physical manifestation of that cause often used as an identifier to treat the specific 'disease' or sickness. Therefore a 'toxin' is something that prevents the normal functioning of cells in some particular way interrupting it in various ways usually by being ingested or imbibed from some outside source presenting with often specific 'symptoms' depending on the 'toxin'. Something incompatible with naturally occurring bodily function.
Boys will be boys. This is the natural course of life leading to manhood. There is no way around it. How can the normal functioning of cells be considered in any way whatsoever the opposite which is defined as a 'disease' or sickness caused by a 'toxin' among other potentials. You are not saying there is a 'toxin' coming from the the outside. You are saying the normal function is the disease. The sickness is healthy and the healthy is the sickness.
Therefore if there is a sickness coming from the outside caused by some specific 'toxin' it is not among the normal functions of the body which in the case of boys here we must refer to as masculinity. If it is toxic, it is not masculinity and if it is masculinity, it is not toxic unless masculinity is what is being referred to as the ultimate 'toxin'. Swap out 'masculinity' with 'femininity' for fun to be presented with the exact same story and toxicity as such can therefore only refer to something that is neither. Something that is animal and misbegotten. Abominable.
Of course people seem to prefer to forget the facts when they decide it suits them.
Fun fact: Nobody particularly cared to catch the Yorkshire ripper which is to say the people charged with the task allowed him to roam free for years and years even catching him and releasing him. No one cared. Until he began to murder women that weren't prostitutes... I guess that wasn't much fun but the fact remains history is littered with these stories and you need not look far to see misogyny and misandry at work in every corner of society to this day.
Why even bother with those separate terms anyway as if the idea someone hates me for no reason actually affects my well-being like the ripper cutting those women up affected theirs? It's self-loathing. Simple. Good times.