Let's say, for example, that I have a Gmail account. I compose and send an e-mail to email@example.com. They aren't using Google services, just so that we can exclude "special cases" where they just keep the entire thing internal to their own network.
On a technical level, doesn't the e-mail client/software just look up somecompany.com's MX records and then connect directly to that IP address on the "e-mail port" and, assuming it is online and accepts the "handshake", just transfers the e-mail directly to it?
Why have I heard all my life that e-mails just get "flung out in cyberspace randomly" and bounced around the entire world, allowing everyone and their grandmother to read it before it finally gets routed to its final destination?
Is this a total misconception? Was it something that was done in the 1960s because they couldn't afford to have computers on at all times, so they had to do it like this? Is it by design in order to allow spying?
I feel ashamed for still not having a good grasp on this after all these years. I've probably tried to ask about this dozens of times over the years, but never got what I considered a clear and conclusive answer.