On an Intel NUC8I7HVK, sudo clr-service-restart -a kills the network connection upon restarting the wpa_supplicant service. The device is not connected to ethernet.
That sounds like intended behavior. clr-service-restart automatically restarts services that are safe to restart (i.e. won’t cause user disruption) and leaves the restarting of the rest of the services up to the user (or reboot) for an opportune time with the understanding it may cause disruption like you described. clr-service-restart -a will restart all of them regardless of whitelisting.
You can also specify which services are or are not able to be automatically restarted.
https://docs.01.org/clearlinux/latest/guides/maintenance/restart.html
@puneetse is correct - if you want to “safely” restart services that are known to safely restart, just do sudo clr-service-restart. The other services will then be skipped. This is what swupd update does after an update.