I suspect we're approaching this situation for numerous types of communication.

If you think about it, the whole "we're going to overnight the offer letter via FedEx" thing is a well-established variant of this trick. It's less about the 48 hour service than the fact that spoofs cost $10 a pop, and would be unlikely to manifest in volume (though of course targeted attacks might occur).

Similar for regular USPS, though that hit's only $0.68 presently.

Ultimately a lot of this generative tech stuff is just counterfeiting extra signals people were using to try to guess at interest, attentiveness, intelligence, etc.

So yeah, as those indicators become debased, maybe we'll go back to sending something in an onerous way all boiled down to bullet points.