An interesting theme here in the comments (that I am sympathetic to) is "TUIs have steep learning curves but are fast/efficient for people with proficiency". I wonder if a small part of the modern preference for GUIs is related to a lack of employee retention. If companies aren't necessarily interested in working hard to keep employees then training new hires needs to be faster/easier and that could work against TUI and keyboard-based tools.

Of course, if that's a factor I'm guessing it's a small one in comparison to expectations about what "modern" software should look like.

What I heard from one large chain is they couldn't train warehouse employees on the green screen (3270) inventory app, its too different for them. They just wouldn't do it or would quit.

It's also quite common that the customer is now the one that drives the interface.

It's the customer's time wasted by the UI, but also the customer typically can't be expected to perform enough orders to actually learn a complicated interface.

TUIs persist in industries where there is specialized knowledge needed to even complete the order. For example, an optometrist's office.

I don't think it's an either/or situation.

An application I worked on was a GUI but (at the user's request) we loaded that thing up with hotkeys like no other.

Watching experienced employees operate a gui I worked on was a fascinating experience. They were so fucking fast!

I think the problem is that GUI authors often put hotkeys in as an afterthought.

This is a definite reality and headache. The learning curve was steep and I literally had somebody walk out after training them for less than two hours.