Hello Anthony,
Indeed, the report category was removed in Studio Pro 10 and now is considered deprecated:
https://docs.mendix.com/releasenotes/studio-pro/10.0/
If you want to generate PDF reports in your application, you may consider use:
https://marketplace.mendix.com/link/component/211553
instead. Please be aware that this module is currently still in Beta.
If this is a limitation, the option is use Studio Pro 9.24.X.
See the docs:
https://docs.mendix.com/appstore/modules/document-generation/