Spam!
Airlines have allowed their various opt-in email communications to devolve into basic spam programs.
Long ago, I used to eagerly open airline emails because I knew there was a good chance that it contained something of interest to me. They used to have regular, recurring weekend getaway fares that were
actually attractive fares. Also, when they emailed a "fare sale", there was a good chance that it actually included sale fares.
If I had ORD set as my home airport, the email might have $159 R/T to SFO or $299 R/T to LHR or CDG. Something a bit interesting...not just a "normal" leisure fare that I could always find on the website.
Now it's just spam. They send so many more emails that don't contain actual sale fares that I rarely open any of them. I've taken to unsubscribing from some.
Some websites try to help by allowing you to set routes and target fares for alerts. So if ORD-LHR drops to $299 on any airline, Kayak (or whatever) will email me. That's fine and good...but I'd still be willing to open an email and read about a fare sale
if I knew it was a legitimate fare sale.
I guess I'm not asking for any new functionality: just a more restrained use of emails. Unless there are different checkboxes: one for "Email me all fare sales" and a 2nd one for "Just email me the really good ones, like the one you usually announce in January for January-March travel."