Men and boys who are naturally masculine and less emotional are told their character is a result of social engineering.
All humans are different and have different levels of expression for different traits, everyone understands this and I don't see anyone denying this. There are some men who are naturally less emotional just as there are women who are naturally less emotional as well... this isn't focused on because it's not a problem, it's really not the point. The point is that society constantly pushes the idea that men should not express their emotions at all. All men are influenced by this... everyone in society is affected by these ideas, even a man who is naturally less expressive. Addressing this fact doesn't erase the people who are naturally less expressive, no one is telling them that they are only a result of social engineering, they're just pointing out how society affects everyone.
The definition for what even constitutes masculinity is already shrouded in contention, so what is "toxic" for one person is not necessarily so for another.
It is objectively harmful to tell boys that men are violent by nature... or that they should not express their emotions. These exact ideas lead directly to repression, violence, and anger... it's unhealthy. It's not really subjective, these are real issues that have been identified across the board that are harmful to men and boys (and consequently women)... You can call it whatever you want, I don't even typically use the term "toxic masculinity", but these issues need to be addressed and resolved.
it's the vocal minority who get to project their views to the public and more often than not, their broad rhetoric does not make a distinction between "toxic" masculinity and maleness.
Feminists do make a distinction, that's precisely why they address these issues as specifically "toxic masculinity" and point out that they are a result of sexist social conditioning. The problem is not due to men or their "maleness", the problem is with what some of the things that society considers to be masculine. There are some harmful ideas that are encouraged as masculine and they really shouldn't be. Society pushes harmful ideas onto children about what they should be or do and it leads to major issues. What feminists want to do is remove these toxic and harmful ideas so that children can grow up and be able to express themselves positively and healthily without any sexism holding them back or causing issues. Once you get rid of the toxic ideas, you are left with a positive expression of masculinity and femininity.