I don't know what's the name of this phenomenon but it reminds me of bass-boosted stereos and over-saturated TV screens. Objectively, from a signal processing theory standpoint, it's not superior to a properly calibrated monitor. But subjectively it seems that we collectively like it when dynamics get crushed to loony-tunes levels.
I feel like HTML email is the same way. People think they want it, but in my experience it's an absolutely abysmal experience. Ever been forwarded one of these corporate-type emails where people reply all over the place, each using their own convention of color and typesetting and emphasis markers, with bits of "rich text" signatures and images littered throughout? That's a bloody terrible experience.
Not that plain text email can't be messy, but it's really a situation where less is more. People have to be a little more careful with what they're doing instead of saying "I'll just write this in neon pink and they'll get it".
As for marketing campaigns then yes, I grant you that you can make much more compelling content with more advanced technology but as far as I'm concerned that's cancer so I don't really care about that. I don't really get why anybody would opt into receiving what's effectively spam into their mailbox although maybe I'm wrong about that.
