Yes, you can remove objects from the Migrate Files/Attachments to Azure feature using a Blacklist. Follow these steps:
- Go to the "Migrate Files/Attachments To Azure" Tab.
- Look for the "Migrate Now" section.
- Under the "Migrate Now" section, you will find the option for "Blacklisted Objects."
- Select the objects from the dropdown menu.
- Click on "Search."

- Now files/attachments will not search in blacklisted objects.
P.S. Discover Azure Integration, the easy way to upload files from any Salesforce record to Azure. Find it on AppExchange: https://appexchange.salesforce.com/appxListingDetail?listingId=c9e71bd6-5bab-4182-a461-b82d4f971183