ISP relations in a nutshell
Senders: You’re blocking our mail, why?
Receivers: Because you’re spamming, stop spamming and we won’t block you.
Senders: But we’re not spamming. What do you mean we’re spamming! How could we be spamming, we’re not sending spam!
Receivers: You’re doing all these things (generating complaints, sending to dead accounts, hitting spam traps, not bounce handling, etc) that makes your mail indistinguishable from spam.
Senders: But we can’t tell what we’re doing wrong unless you give us more data!
Receivers: OK, fine. Here are FBLs, postmaster pages, sender access to support people. Now, stop spamming.
Receivers: It’s costing us how much to provide support to senders?!?! And after years of giving them lots of data it’s still the same problems over and over again? We’re not a charity, we’re going to control our costs and stop providing so much personal support.
And that, readers, is why receivers are pulling back from providing the data they used to.