They are commonly called split rims, whatever you say. Your wealth of knowledge is easily overrun by your insistance on correcting every percieved error that anyone happens to post. I could really care less because 99% of the people that I know would describe those rims as "split rims" regardless of whatever the manufacturer described them as 70 years ago, or you do today. I don't need your lectures.
I fully understand the dangers they pose, a very talented, salt-of the-earth type of guy I used to know had his head torn off by one of those rings about 10 years ago.