It's possible to add default content to document sets. This functionality works just fine when creating new document sets from the document set content type.
However, when the default content needs to be modified or deleted it's impossible to do so in sites that are enabled for NoScript. You get the access denied page "Sorry, you don't have access" when you try to delete a default content document and press OK in the document set advanced settings page.
This has to be an oversight as it makes no sense that it's allowed to add default content but not delete it without disabling NoScript on the site.
Can Microsoft please fix this?
This is on SharePoint Online, but I believe the same issue is present on SharePoint 2019.