well, actually nobody gives a shit, use whatever you fit best for the task.
For me to be able to use whatever I want, it needs to exist. Therefore it is a relevant discussion to have, since it might influence a developer to consider TUI instead of just going for GUI as the default.
Waiting for others to do something for you is the wrong approach. Get off your ass and be the developer. Creating an interface for a tool is no rocket science.
I generally agree but it depends on the application and the computer purpose / input you will most use.
Like.. it doesn't make much sense to have a CLI/TUI for an image editor.. if you start using things like sixel you are essentially building a GUI that runs in a terminal, not a TUI. The same happens with videogames, video players and related entertainment applications.
But like I said, I do generally agree. I'd even argue that when possible, GUIs should just be frontends that ultimately just call the corresponding CLI programs with the appropriate parameters, avoiding duplication.
Also, GUI always has feature creep. The story would be different, if they would keep to the do one thing well principle of cli.
Because there's no convenient framework the user can just plop new functionality in, like shell is one.
Well, there is, kinda. But webbrowsers are the antithesis to do one thing well.
I use 
BTW
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
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