
Still a lot of ancient industrial hardware that needs it
There is still a lot of old industrial equipment out there that needs IE for control, because its control software was specifically coded for IE's defects. And since the hardware is no longer sold they haven't updated the control software and want you to just replace your entire cooling system so you can have new control software. Manufacturers like Eaton, but they're hardly the only ones.
I know a guy whose coolers and radars all broke with the early May Windows 10 update. They need a specific ancient version of Java (JRE-6u35) running an applet on actual Internet Explorer. No Chrome, no Firefox, no Edge. They also need Flash for some other stuff (lawl). He had over SIXTY of these pieces of old but functional kit that were no longer working. Money to replace them all is... not in his budget.
So what I did for him is make a 32-bit Windows 7 VM with that version of Java and the last working version of Flash (32.0.0.371). The image is 'only' 3.5GB. They run it on VirtualBox on their Windows 10 machines. VirtualBox allows you to pass through things like USB devices and COM ports. I was a little worried, but they say it works. And since MS doesn't update Win7 any more, it won't break randomly.
Anyhow, as long as this old stuff is out there and running and needs IE, IE will shamble on. It's the ultimate outcome of MS making IE deliberately non-standards conforming so they could dominate the browser market, and companies then making things that only run on IE. They deliberately created this situation, now they can deal with it (badly).