Also, a Windows ISO can’t be bundled because that would be a violation of Microsoft’s license, so Qubes Windows Tools coming prepackaged wouldn’t make much sense, and it would be unnecessary bloat to the ISO with the optional install when some users don’t even make any Windows VMs.
This is because Debian and Fedora are officially supported by the Qubes OS team, whereas all other templates are community supported. You need to enable a different repository for them and extend your trust to more people.