Any reasonable email reader will allow you to turn off HTML, execution of Javascript, and any resolution of outside URLs. That render email pretty safe. It's how I've been doing email for decades.
Yes, plaintext email is awesome! Too bad most major providers hide the option (or straight-up don't have it).
I'll just plug https://useplaintext.email as a great resource. The main recommendations are... opinionated (this site is run by Drew Devault, after all), but the instructions are very useful. I personally use thunderbird.
