Same here. This is one of the biggest selling points for macOS as a power user. I've used Windows and linux for years, and continue to do so on a daily basis. But on macOS, one can absolutely fly due to the consistent keyboard shortcuts.

- Standard keyboard shortcuts across all apps: done

- Standard Unix/bash shortcuts for moving the cursor/manipulating text: done

But, to the OP's point, unless you invest the time to learn how they work in macOS, they'll largely remain hidden and unknown.

When helping friends and colleagues transition to macOS, explaining how keyboard shortcuts work (and how powerful they are!) is the first thing I do--followed by the window/app paradigm, and then Finder.

As far as discoverability, you can use Command+Shift+/ pretty much anywhere. That keyboard shortcut displays the Help menu for the current application, with the search box already focused.

So, for example, in the Mail app, if you wanted to forward an email:

  Command+Shift+/. Start typing "forward"

Then hover your mouse over the "Forward" result. You'll immediately see the location in the menu bar, along with the corresponding keyboard shortcut: ⇧⌘F (Shift+Command+F), in this case.

And, of course, Command+; will open the Preferences for any application.

Apple actually has fairly great documentation on standard keyboard shortcuts [0].

[0] https://support.apple.com/en-us/HT201236