> I’d guess that this is a cost-cutting move, as it’s much cheaper to offer push notifications from their app than it is to send out SMS. I'd have to second this guess. SMS is much more expensive than push notifications.
In all such cases the cost of engineering/operations time to keep these services alive overshadows pretty much everything else. So it's not cost per SMS that they are worried about, but rather the time spent maintaining and fixing these systems compared to how much they are used.
This is an extremely aggressive claim that I doubt holds up.
I would absolutely agree with "In _many_ such cases", or "In _most_ such cases", but it's almost certainly false to claim "In _all_ such cases".