It's not just shortcode using admins who don't want to use Gutenberg. There are many people who have used any one of various visual composers for years. They generally don't have the time or inclination to learn a new workflow that doesn't support what they already do.

Having a classic editor plugin has nothing to do with characterizing people as crufty throwbacks who can't learn new things. Many people are in the business of their business and don't care to learn the next new-greatest-software every few months.

Yes, I get it. I've used Elementor, DIVI, Beaver Builder, WPBakery , ... And I always hated when I had to switch to a new builder for some new project.

Seconding this, end users do seem to like how much they can do themselves with it

Especially when you add custom blocks specific to their site needs