To hide the "Queries and Connections" section from the ribbon, you could use a Custom UI XML file and add it to your Excel file (more details on how to do that in this article).
Before:

After:

I'm using Excel 365, so the following worked for me:
[FileName: customUI14.xml]
<customUI xmlns="http://schemas.microsoft.com/office/2009/07/customui">
<ribbon>
<tabs>
<!-- Set visible to false for the Queries and Connections on the Data tab-->
<tab idMso="TabData">
<group idMso="GroupDataQueriesAndConnectionsWorkbookLinks" visible="false"/>
</tab>
<tab idMso="TabData">
<!-- Replace the group with an empty one -->
<group id="DupGroupDataQueriesAndConnectionsWorkbookLinks" label="Queries && Connections" insertBeforeMso="GroupDataQueriesAndConnectionsWorkbookLinks">
</group>
</tab>
</tabs>
</ribbon>
</customUI>
This code is inspired by this answer, but I've left the group empty since we don't want any buttons there.
If you are using a different version of Excel, you might need to replace GroupDataQueriesAndConnectionsWorkbookLinks with a different group name. Note that you can find a list of the official group names in this repository:
https://github.com/OfficeDev/office-fluent-ui-command-identifiers
(Select the folder corresponding to your version of Excel and download the file excelcontrols.xlsx).