You don't recall the (long) period throughout which Windows would run *any* kind of executable file it was given by Internet Explorer, and while IE only bothered looking at the file extension *listed in the multipart header* to decide whether a file was safe to run? Not a script in sight, the culprit was the IFRAME.
My aversion to HTML is that what you see isn't what you get, and there's no way of knowing what bugs lie within even sanely-written software. I particularly don't want web bugs spreading details about me even more widely than at present, so none of my email or news clients render HTML.
HTML is no more 'modern' than plain text, it's just designed for a different purpose. Its use in plain-text media such as email and NNTP, where pictures are unnecessary and hypertext links rare, is simply a sign of ignorance.