> 古書店の店主であるこの老人は、相手が誰であろうと笑顔 **というもの** をまったく見せない。

Am I missing some nuance here? What if I removed というもの? How would it change?
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2023-02-04T11:49:03.347
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2023-02-04T12:34:19.153
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question
grammar
What does というもの mean here?
This might work as a very rough translation.

"The old gentleman and purveyor of second hand books was unacquainted with
that thing commonly known as a smile"
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2023-02-04T12:12:08.353
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2023-02-04T12:12:08.353
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answer