Meaning of “Ryousan gata(量産型)”
“Ryousan gata(量産型)” means “common type” or “ordinary type” or “not special”.
“Ryousan(量産)” means mass production.
“gata(型)” means type.
It’s not a slang but it’s sounds like slang.
“Ryousan gata Joshi(量産型女子)” means a girl who do the same thing with others.
“Joshi(女子)” means girl.
They wear the same type of makeup with others, and same type of clothes. So it might be difficult to recognize, everyone looks almost same.
Why they do same thing with others? Maybe it’s a safer choice than choosing something different from others.
You know, Japan is agricultural society and we should keep harmony basically.
Someone doing something different from others can be a target of bully.
So “A nail that stands will be hammered down.”.
A: Girls in our class are “Ryousan gata Joshi(量産型女子)”, aren’t you?
B: Yeah, and we are “Ryousan gata Otaku(量産型オタク)”.