Is it really? Who can read it today? Your email provider and theirs? Gmail won't deliver messages without TLS any more, so everyone supports it or they're effectively kicked out of email.
> Who can read it today?
It's true that email isn't quite as insecure as it used to be (it was once compared to shouting your message at someone and expecting them to shout it in the right direction until it reached the intended recipient), but there are still many things missing compared to other forms of direct messaging, and there's good reason why many people and organisations don't want it used to send sensitive information.