Hi @Carl Williams ,
Per my test, if you are using OOTB, it is indeed the behavior by default.
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If you want to use json formatting to customize the hover of the column, some can be achieved.
For example, to realize the preview of the picture you can use the json mentioned in this link:
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Per my understanding, adding Rating field to the hover card is currently not supported. I would suggest you go to SharePoint UserVoice to make your suggestions.
From another perspective, you could also try to use the Rating Settings that SharePoint itself has.
Go to Library Settings>Rating Settings, and enable the Rating settings:
After this step when you change the library view, you will see the Rating column:
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