Are there any disadvantages to including many attributes in the Planning→Attribute Mapping configuration?

In our environment, we have not changed the "Attribute Mapping" section of the Planning configuration data group in quite some time. My team inherited maintenance of the CLM Suite from another team and they evidently were more diligent about updating the "Attribute Mapping" section than we have been. We've added many custom attributes, but never added those custom attributes to the Attribute Mapping section. On the other hand, there are probably two dozen custom attributes that were added to this section by the team before us.

From reading the help content, it sounds like the purpose of the Attribute Mapping section is to define which attributes are available for display as a column in a plan view. I am assuming this is because plan views are built from an index and you need to configure RTC to store these attributes in the index in order for them to be available. Is that a correct assumption?

If the Attribute Mapping affects the lookup index when viewing a plan, is there any performance penalty or disadvantage to having multiple attributes included in the Attribute Mapping list or is this list pretty tolerant of growth? I have to assume it's at least somewhat sensitive or RTC would just add all attributes to the Attribute Mapping automatically by default.

Edit: This question came up again for our team today. I came back to this question to see if I ever got a response and didn't find one. Hopefully this edit will bump the question back to the top.