It's also like saying you don't believe house fires actually happen because yours hasn't "ever in over 20 years, even once"
That has been a problem for a long time too, but it's been a progression. I remember att.com and aol.com blocking mail from legit but small mail servers of my customers since decades ago. It was only a few hosts doing blocking, and they were blocking more selectively like only blocking Road Runner cable modem ip's not all small mail servers. And today it's just a lot worse in both dimensions.
If you never encountered this problem in 20 years, for 15 of those years it just means you didn't happen to encounter one of the few examples, now there are more examples but many of those are new and so you've only had to be lucky not to encounter them for a short time.
This is how a lot of experience gives a false indication. Not encountering a progressing problem like this for 20 years is not like "I've cooked spaghetti this way for 20 years"
No, that is not what I was talking about, nor the comment I was replying to.
I was replying to this:
> Credit card companies calling me because they think I'm committing fraud, retail sites cancelling my orders because they think I'm scamming them
Anecdote aside, I've had several people not receive my emails at all, some I've been able to actually test, using Tutanota for outbound messages. I've created or helped create Teams accounts for others several times in the past and have never run into anything like this with any other provider. Microsoft is setting a precedent by singling out one provider. I hope it's not a sign of things to come. Virtually all email is de-facto controlled by a Microsoft/Google duopoly.
I looked into running a personal email server on a home machine once and was put off by how many people told me my messages would be undelivered without numerous hoops to jump through.
What a mess.