What got so complicated? Things like reverse PTR and SPF are trivial. DKIM is a bother to set up but you do it once during an annoyed afternoon and never need to look at it again. DMARC is as easy to set up as DKIM.
> why isn't our mail just routed to a three-word address?
If only there was something that could take words like "grdotcloud gmail com" that we could use to deliver mail!