I can’t see how either of those examples are social engineering. If a genuine business is so foolish to not have a phone number how would they do business? Even if it was so vote with your feet and deal with others. We will not get service from business unless we demand it.
Trying to eliminate paper invoices is a growing trend, the motive is money nothing more. If you count that as social engineering (which I don’t) it has been going on for millennia and didn’t need to the digital era to bring it on.
At long last after the IT industry started spruiking about the paperless office it is starting to happen but the motive is just money whether private or public. I suppose there was a time when people resisted having to get a telephone but it became standard in time. The same will happen to digital communications.
