LB – whether or not what your Rabbi is saying is true would depend on how he is defining Chareidism. It is probably quite possible to define Chareidiism in such a way that what he is saying is true.
For example, if he were to take a specific aspect that is commonly found in the Chareidi world and to say that that defines Charediism, then he might be right. But the question is: is that the most accurate or apprpriate way to define Chareidim? I agree with Joseph that today the term is basically used merely as default Torah Judaism.
I remember once many years ago when my friend’s Israeli Chareidi husband wanted to set me up with a cousin of his from B’nei Brak and I was concerned about the fact that he was Chareidi (which I thought meant some specific brand of Judaism). He was like, “why? Do you watch tv?”
I had similar reactions time and time again whenever such conversations too place.