You’re right, of course. In fact, one could conceive of a language where the grammatical number of the object would have to agree with the subject, and it would therefore not give any information about the actual number of things denoted by the object, which would have to be stated explicitly if it’s necessary to avoid ambiguity, like in languages that lack grammatical number altogether. For all I know, there might even be an actual human language somewhere that features something like this.
You’re right, of course. In fact, one could conceive of a language where the grammatical number of the object would have to agree with the subject, and it would therefore not give any information about the actual number of things denoted by the object, which would have to be stated explicitly if it’s necessary to avoid ambiguity, like in languages that lack grammatical number altogether. For all I know, there might even be an actual human language somewhere that features something like this.