Talking specifically about a “blue house” doesn’t make all houses blue. It doesn’t even imply that all houses are blue.

Talking about an “Asian women” doesn’t make all women Asian, or even imply that all women are Asian. It refers only to Asian women.

Talking about “toxic masculinity” I think is a reference to only the “toxic” bits of masculinity, and has no bearing on masculinity as a whole. Talking about “toxic masculinity” is not intended to be a jab at men, or masculinity. It is not saying that all masculinity is toxic (there are “toxic” parts of everything, A mostly good thing can have bad bits).

“Toxic masculinity” is the blue house.

Or the multicolored polka dot chrome house. Which is certainly not a large proportion of houses.