Having WAN 2 (2nd of 2 ISP connections) monitored is requirement to achieve HA for SD-WAN. Once you have more than one WAN connection without an alert on BOTH WAN circuits you may not even realize you have an ISP outage on WAN 2 until the WAN 1 fails. However when this occurs the device is unreachable so you get another alert for that.
Request feature change as follows would be to
alarm on "ANY WAN" failure
and
to reduce events that recover set a timer of 5,15,30,60 minutes before alarming.
Corrected per @PhilipDAth feedback