Consider this as a guest os level restart. Upgrading from vSphere 6.7 to a higher version (6.7.x) don’t required any hardware reboots and it saves time an Esxi host spends in maintenance mode during remediation. So whats enhancements vSphere 6.7 brought for VUM? You can read those posts from below links:

I have written few posts on vSphere 6.7 earlier. Isn’t it exciting to get rid of flash based Web Client (yeah screw that VMware !!!) VMware is working hard on incorporating all the VUM features in the new HTML5 client as soon as possible and we might see them in upcoming updates of vSphere 6.7. Not all the features are available in HTML5 client and few features like VUM configuration changes, VMware tools upgrade etc can only be performed via vSphere Web Client (flash). With vSphere 6.7, VMware integraded few of the VUM funtionality in the new HTML5 client. With the release of vSphere 6.5, vSphere Update Manager (VUM) was inegrated with VCSA which made customers very happy as we no longer needed an additional windows server for installing VUM.

Esxi 6.7 vmware tools download