https://learn.microsoft.com/en-us/power-bi/visuals/power-bi-visualization-export-data?tabs=powerbi-desktop The export functionality can be disabled on several levels. First, Power BI Service admins can disable this functionality on tenant level. With that, nobody will be able to export the data. More about that later. Second, as a dataset owner you can decide if you allow your users to export the data. This is managed in dataset settings, but only changeable in Power BI desktop.
No matter what settings are applied in Power BI desktop, the tenant settings will overrule this. In the end the Power BI Service admin decides what options are possible to use.
https://data-marc.com/2020/04/13/power-bi-governance-why-you-should-consider-to-disable-export-to-excel/