Firstly, isn't that victim blaming? The man is dead. Why blame them (their masculinity/masculinity as a whole) for their own death? That seems like a horrible thing to do in my opinion, like stomping on his own grave.

Secondly, if anything is toxic then it's the society that put men in that place where they thought suicide was the only option. Toxic society towards men = toxic masculinity I guess...

Which brings up my last point. Toxic masculinity is often characterized by men "not wanting to show emotion" which I can explain with this.

Also, if men show their emotions to the wrong people they can get those emotions thrown right back at them. If anger, then they might be called an abuser (I have). If sadness or depression then they might have their partner leave them because they aren't being strong enough (happened to me too).

A female partner leaving a man for showing weakness is toxic femininity, a man not wanting to expose his weakness for fear of the toxic femininity is just protecting himself.

TL:DR

Toxic masculinity is a way to brush male problems big enough for them to kill themselves (like MGM) under the rug and blame men as a group for problems that happen to other men (as a result of society or women abandoning them).