Removed. Thanks :)

This is just for security issues. A member with a sysadmin account is able to delete projects. I agree that it needs to show that somewhere.

Some of its subprojects do contain some data(not much but there is data) so maybe we should keep it as it's not causing any problems?

Thanks for your reports. Apologies for my delay but I'm busy with exams at this time.
As for this issue, projects are not always assumed to have a git repo. All projects you see have a git repo just because they're all fetched from kde_projects.xml but you can define a project with no git repos and everything should work fine.
I have now updated Calligra project to have no git repos. I see that this caused the overview page to not be displayed but this is another issue that I have fixed now.