If this setting is enabled, then the remote access host compares the name of the local user (that the host is associated with) and the name of the Google account registered as the host owner (i.e. "johndoe" if the host is owned by "firstname.lastname@example.org" Google account). The remote access host will not start if the name of the host owner is different from the name of the local user that the host is associated with. RemoteAccessHostMatchUsername policy should be used together with RemoteAccessHostDomain to also enforce that the Google account of the host owner is associated with a specific domain (i.e. "example.com").
If this setting is disabled or not set, then the remote access host can be associated with any local user.