I'm also not sure about why multiple notification channels can't be used. If there's an alert I'd like to be notified by all means possible (depending on severity)
This definitely seems like something that's more about development priority that they're trying to sell as a feature....
Realistically, since they just autoescalate if the incident isn't acknowledged it appears, one would think any/all notification methods would be a positive. Let the user (or their manager...) sort out what method(s) works best for them.
