Google--a technology giant with algorithms and heuristics running most operations--is not up to the task of improving algorithms for email server reputation? No, they are definitely capable of improvement. It's simply not of interest to them.
I can hardly blame them because the cost-benefit analysis clearly says, "why bother?"
Of course anything can be gamed, but magnitude matters. I've had the same domain for 24 years, with many hundreds or thousands of email conversations between users of my server and those of the major email players over the years. I had to switch my mail server's IP address two years ago. Immediate zero reputation from many big players.
Incorrect, if they stopped spending all that money and effort to keep up, their users would get flooded.
> Of course anything can be gamed
Sending spam/marketing e-mails is a multi-million industry. Both on illegal and legal markets. It's a constant race.
This isn't the 1990's anymore, recipient domains aren't just homes to a few hundred undergraduates or a dozen programmers. Email hosts manage communication for hundreds of millions of customers.
That algorithm doesn't work. The internet is filled with parked domains that have "never been malicious". This just creates a new market for clean domains that you can use to evade protections. It makes spam a little more expensive, but it still gets through.
None of these tricks work. There are no tricks. All rules can be gamed. The only thing that can't be easily faked is reality: if Microsoft knows you're a big org with a well-managed IT group running your output email setup, then they know they can (probably) trust you not to spam their customers. If you are too small to prove that to MS in a scalable way, no amount of heuristic trickery is going to help you.