いちがい一概ichigaiにni
1.
In a manner that disregards specific differences and treats all instances uniformly, often used in contexts where such generalization may be misleading or overly simplistic.
2.
In a way that entails making a judgment or declaration about a group without considering individual variations, typically accompanied by negative implications regarding the validity of such conclusions.
3.
Without differentiating individual cases or conditions, leading to a broad, sometimes inappropriate, categorization or assumption about a particular subject or situation.
Example:
そうですね。一概には言えませんね。