Some users think Virt-Manager is deprecated, But according to:
TL;DR: I’m the primary author of virt-manager. virt-manager is deprecated in RHEL8 in favor of cockpit, but ONLY in RHEL8 and future RHEL releases. The upstream project virt-manager is still maintained and is still relevant for other distros.
Only will effect RHEL, Not the upstream or other distros.