It depends who is your target audience. For me, TUI interfaces (Text UI like Weechat, Neomutt, Cmus, ...) are beautiful and easy to use. They are straight to the point, keyboard based, extremely fast, low on resource usage, ... I'm so much more productive on this kind of interface than GUI/mouse based ones.

GUI tends to be slow, buggy, unresponsive, less configurable, heavy on resources, ... So much code required to manage GUI interface compared to code doing real business stuff. So much wasted clock cycles.

I have a laptop with 64GB of RAM but I don't want to waste this RAM to display "beautiful" GUI apps. I need it for things more useful like VMs, processing big files, ...

I want to be productive. Not wasting my time with the latest UX "experts" enlightenment on what a "modern/futuristic" interface should look like.

BTW, Get off my lawn :P

EDIT: For your question... Would I pay for a more beautiful app? No. Would I pay for a software that have features I need that are not already available in software I use? Yes (don't care about how beautiful it is).