My kid’s school sends out e-mails where the text is rendered as a CDN-linked image in the text/html part of the message. The text/plain alternative part of the message is an incomprehensible list of long URLs to their CDN, though an "unsubscribe" link is also provided. I can view the images, but this is clearly an accessibility fail. And really, is it too much to ask people to send the text of their e-mails *as* text?