> Transient UIs [...] could usually be replaced by just using a regular special-mode keymap in a custom buffer.
For people who can look at a list of key bindings once and have them memorized, maybe. Turns out most people are not like that, and appreciate an interface that accounts for that.
You also completely ignore that the menus are used to set arguments to be used by the command subsequently invoked, and that the enabled/disabled arguments and their values can be remembered for future invocations.
> The fact that Transient hooks into the MVC and breaks elementary navigation such as using isearch
Not true. (Try it.) This was true for very early versions; it hasn't been true for years.
> or switching around buffers
Since you earlier said that transient menus could be replaced with regular prefix keys, it seems appropriate to point out that transient menus share this "defect" with regular prefix keys, see https://github.com/magit/transient/issues/17#issuecomment-46.... (Except that in the case of transient you actually can enable such buffer switching, it's just strongly discouraged because you are going to shoot yourself in the foot if you do that, but if you really want to you can, see https://github.com/magit/transient/issues/114#issuecomment-8....
> has irritated me ever since Magit adopted the new interface.
I usually do not respond to posts like this (anymore), but sometimes the urge is just too strong.
I have grown increasingly irritated by your behavior over the last few weeks. Your suggestion to add my cond-let* to Emacs had a list of things "you are doing wrong" attached. You followed that up on Mastodon with (paraphrasing) "I'm gonna stop using Magit because it's got a sick new dependency". Not satisfied with throwing out my unconventional syntax suggestion, you are now actively working on making cond-let* as bad as possible. And now you are recycling some old misconceptions about Transient, which can at best be described as half-truths.