So under the guise of spam protection, we have created an oligopoly of email gateways, despite sending an email being an utterly trivial, long solved problem, and now those companies are putting the squeeze on. The best part about this particular item on the list of "things that have only gotten worse over time": they charge companies more to deliver what is essentially spam, and they conspired to make that spam show…
It is absolutely not. Even if you are not considering the whole spam thing.
Sending an email with the multitude of clients, MIME which is very complex in itself, network issues, message queuing, retries, unsubscription, bounces, providers feedback loops, rate limiting and what not is very hard.
If you add the whole spam folder + blacklists situation into consideration, sending emails becomes a more than painful thing you don't want to deal with.