not limited to only ~
Expresses that something is not unique to a particular person, place, or situation.
This pattern is used to say that a certain characteristic, problem, or phenomenon is not exclusive to the thing mentioned. It often carries a nuance of correction or broadening perspective, implying that other cases are equally affected or relevant. For example, if someone thinks only a certain group has a problem, you can say それは学生に限ったことではない to point out that it applies to others too.
It is formed by taking the noun or clause and adding に限ったことではない. When you want to contrast with other cases, you often add だけ or のみ before に, but に限ったことではない already includes the idea of exclusivity. The pattern is somewhat formal and is frequently used in written language, speeches, or serious discussions, but it can appear in spoken Japanese when making a logical point.
In conversation, you might hear a simpler version like それだけじゃない or ~だけではない, but using に限ったことではない adds a nuance of 'not being limited to that particular case' and is more emphatic.