“Toxic masculinity” is absolute dog shit as a name for it, and I’m sure the parent commenter is reacting to that.
People use the adjective in plenty of adjective-noun pairs as an intensifier all the time. The ones railing against “deviant homosexuals” are not distinguishing them from the vanilla ones, nor do people who decry “evil pedophiles” recognize and support a non-evil variety. Thus, a lot of people hear the name “toxic masculinity” the same way, as if it is denouncing masculinity as a whole.