> I'd rather say the issue is that the big boys' business is NOT mails, so their goal is to provide the minimum viable mail service, and not spend one dollar more on it.

Plenty of money was spent criminalising crypto by the big boys.

Even disregarding that fact, your equation makes no sense because AOL or whatever big BS you have in mind has null interest providing a product they have to spend money on with zero realistic ROI.

Since arpa net arose eventually from the same party poopers, nothing of this should come as a real surprise.

Mail providers never wrote rfcs. Nor are they expensive, just concensus requiring.

If email was encrypted at rest, gmail would disappear overnight. Gmail's whole purpose is end user data gathering, for profit.

Many other mail providers are the same.