Yes. For as long as it has existed, the Platinum Card has featured a laundry list of unrelated benefits. The marketing theory behind this shotgun approach is that many customers will latch onto _something_ that they value, and disregard the rest. However, they apparently have survey data which shows that many people are unaware of many features. This is why they insist on "reviewing" the benefits as part of the retention process, and why they often promote existing features as if they were new, and I suppose it is the reason they make these calls.
I'd like to believe there's even more strategy to this approach too. So much of this stuff is data-driven. It's pretty intense. Otherwise, cold-calling all of your customers with random info, would be quite the effort. I'd be curious if it was because cancellations were up. Or maybe they are able to identify good clients that are "at-risk" of cancelling. Such as those who stopped using their card. Instead of waiting for the inevitable cancel and retention offer, why not talk about perks their account hasn't used, and has been shown to increase retention? Ie - "Hello, did you know we added a $400 Dell credit?" As you said, many probably don't know this. It's probably also easier to explain it now vs once they have it in their mind that they want to cancel.