I think that’s actually the case. In the many years I used facebook I don’t think I received a single email from them (only from that shitty trip advisor fb app that was spamming me like there was no tomorrow). Like many others here I got annoyed by my facebook feed and simply deleted the facebook app from my smartphone which means I now only connect once a week or less. Almost immediatly I started receiving a lot of facebook spam on my email. Clearly they have an algorithm “shit this user is leaving, let’s try to get him back” (algorithm which effect was only to aggravate my annoyance level). They must be worried about that.

the fewer that people use the network (FB) the less valuable it will be