Standards are important, and the meaning assigned to words are important, but if your very important email does go through, because Google thinks you're wrong, you add the bloody message-id. I really do agree, I don't care about the linguistic/legal/standard/technological reason as to why Google might be wrong, if I can't deliver email to Gsuite customers, I add the message-id.
You're precisely right that customer experience matter, but I wouldn't put it past some conservative European company to go: Well Google is wrong, so they should fix that. Google doesn't care, you can't make them care, you can't even contact them. Just make it work for your customer.
You're precisely right that customer experience matter, but I wouldn't put it past some conservative European company to go: Well Google is wrong, so they should fix that. Google doesn't care, you can't make them care, you can't even contact them. Just make it work for your customer.