The solution is clear to anyone who thinks about the problem and its cause, something that unfortunately you seem to be unwilling to accept. The problem isn't Zen's to fix but rather your e-mail forwarder. Accept that and move on.
Sorry - that's nonsense. It's akin to saying "company Blogs has implemented a change which damages the service to its customers because of a bug in Windows 10, therefore Microsoft should fix the bug" - dream on.
So you would rather Zen not implement a global standard because it means your upstream mail forwarder has been lax in implementing a technology that has been on the horizon for a long time?
That would mean Zen would have to check every single mail forwarder that connects to their systems before they implement it, and that isn't ever going to happen.
The problem is NOT of Zens' making, the problem is poor implementation by the upstream host.
I assume that Zen have also implemented these additions on their outbound too, as I see no complaints from anyone saying their outbound mail has not been delivered then I also assume that Zen have correctly updated their systems to handle SPF etc.
If you have your own domain name and email, then there is some requirement that you manage it from time to time, otherwise get a gmail account!
HG612 -> pfSense 2.4B
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Artificial Intelligence is no match for Natural Stupidity.
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