macOS is my favourite operating system. Finder in column view with arrow keys to navigate, combined with space for file preview, is incredibly fast and intuitive. Trackpad integration also results in less hand movement. I'm building a Linux (Bazzite) desktop, though, and I've set my sights on the stars.
nnn looks to be an incredible file manager, and was a great recommendation. It looks even more capable than Finder, albeit without scrolling/zooming previews, thanks to macOS having unmatched trackpad functionality. Not to mention Spotlight, which makes opening apps trivial--especially with Alfred available as well. I want to go beyond mere file management, though.
File managenent, browsing, gaming, everything. Just how much can you configure a Linux system to eliminate mouse usage? Shortcut guides welcome (I already know the major ones). I also have a keen interest in tiling window managers, but I've not delved that deep yet. I don't know how to set one up.
Guess I'm forced to learn Emacs/Vim/similar.
This might be a controversial opinion, but I would stick with the QWERTY layout. There's already a lot of cognitive overhead learning things like tiling window managers and Vim key bindings that I don't think that switching up the keyboard layout is really worth it. What affects typing speed most, imho, is muscle memory, speed of thought, and lastly finger reach. Ortholinear keyboards help a lot with that last aspect, and there's differing opinions on what is best.
I think a good place to start is learning to use the Preionic 60% or the Plank 40%. Keep the QWERTY layout, but memorize how to access symbols (and on the 40% numbers) using the additional layer keys.
You can think of layer keys like extra shift keys near the space bar that change not just to capital letters, but also numbers and symbols, that's why you can get away with significantly less keys on the keyboard, and gain much faster reach of your fingers once you memorize these other layouts.
The order I would go is:
Learn Vim/Vimium on a regular keyboard. Learn how to use the terminal to do as many everyday tasks as you can.
Customize and learn to use a tiling window manager on a regular keyboard.
Buy, build, and learn to use an ortholinear keyboard with the tiling window manager.
After you're comfortable with that, you can consider installing the different layouts like COLEMAK onto your ortho and try that out. But honestly I don't think this last step is necessary. Instead I'd start to look at other ortho keyboards you might like more than the preionic or plank.
I now use the ZSA Voyager. My friend enjoys using a custom ortho with a curved surface for ergonomics. And there are typing devices called DataHands that basically completely upend the way one thinks about typing. Its a whole world. Good luck.