It's what the default is. TUIs default to fast, stable, high-information-density, so you have to real work to make them otherwise. And I say this next part as primarily a front-end developer the past few years: web apps default to slow, brittle, too-much-whitespace "make the logo bigger" cruft, and it takes real work to make them otherwise.

At the end of the day most people are lazy and most things, including (especially?) things done for work, are low quality. So you end up with the default more often than not.

Easier to sell the initial impression for "modern" web apps (shiny, easy-to-learn, low-skill-ceiling) vs the actual performance of TUI/"desktop" apps (mundane, effortful-to-learn, higher skill ceiling).

Maybe someone has examples of web apps made for also a high skill ceiling?

I've heard Linear, Superhuman does something like that while maintaining a nice interface, but I've never used those

in my experience, many managers tend to try to dumb products down as much as possible, to make it work for the most people. the problem is that this, together with the usual bad ui/ux, makes the product inefficient to use, especially for power users.

then, every couple of years, a startup tries to carve out a niche by making a product that caters to power users and makes efficiency a priority. those power users adopt it and start to recommend it to other regular users. this usually also tends to work quite well because even regular users are smarter than expected, especially when motivated. thus the product grows, the startup grows and voila, a tech giant buys it.

now one of the tech giants managers gets the task to improve profits and figures out, the way to do this is to increase the user base by making the product easier to use. UX enshittification ensues, the power users start looking out for the next niche product and the cycle starts anew.

rule of thumb: if the manager says "my grandma who never used a computer before in her life must be able to use it", abandon ship.