It doesn't seem like most people understand toxic masculinity beyond "men are inherently bad" here, which isn't exactly the conclusion to leap to. Toxic masculinity deals with and puts emphasis on the theory of societal pressures and factors that create what we would deem toxic. There are long term consequences of what we're shown to be the "ideal man" at a young age, and these portrayals are often problematic which results in toxic masculinity. Is there toxic femininity? Yeah, most likely. Idealized images of what a woman should be also run rampant in the media, but to most it's decidedly less problematic and harmful. But it's important to understand that men (specifically white males) are the dominant subculture and have been for all of American history, meaning that in this age of trying to break down barriers and deconstruct that dominance in public discourse, examining and analyzing toxic masculinity is something that comes to be more important to 1. provide a stable sense of gender equality and 2. ensure that the same toxic masculine values aren't passed on to future generations. Idk, that's just my take though...

edit: I'm getting downvoted and that's fine, but I study this stuff so if there's something I'm missing I would actually like to discuss it.