Keyboard mapping is fine on macOS (though most of those posts seem related to software or functionality I would never use). Keyboard-only experience is a lot more than keyboard mapping.
Consider window management, for example. If we're talking about using the keyboard for nearly everything, window management is one of the most fundamental parts of interacting with a computer. Linux has dozens of keyboard-based tiling window managers. You have only a few options on macOS, and they are all weak by comparison. Yabai is passable if you partially disable SIP so it can manage spaces, but it still has pretty limited functionality compared to herbstluftwm and bspwm (which is what it's mimicking) and feels hacky.
Similarly, cli tools are very popular on linux, and it is very easy to bind keys to them. Luckily a lot of tools work on both linux and mac, but this is not always the case. Replicating my global hotkeys has been an annoyance on macOS in some cases because of this. In linux, you have control of and multiple options for basically everything (e.g. bootloader, what you use for networking, what you use for notifications, etc.). In the case of notifications, on linux I can just bind a key to "dunstctl close-all" to close all notifications or "dunstctl history-pop" to show old notifications. My notification daemon is designed with scriptability in mind. If I want to have a similar keybinding on macOS I have to go through an arduous process of trying to find some up-to-date applescript snippet that actually works and isn't slow (couldn't find one that met either requirement) or learn to use some other automation tool. Unlike the WM case, I'm sure it's possible, it's just that macOS is just very clearly not designed with the use-case of keyboard for everything in mind. It can still support it very well, but with linux I can have it so that non-keyboard-friendly software just doesn't exist on my system. I don't need to workaround it.
Consider window management, for example. If we're talking about using the keyboard for nearly everything, window management is one of the most fundamental parts of interacting with a computer. Linux has dozens of keyboard-based tiling window managers. You have only a few options on macOS, and they are all weak by comparison. Yabai is passable if you partially disable SIP so it can manage spaces, but it still has pretty limited functionality compared to herbstluftwm and bspwm (which is what it's mimicking) and feels hacky.
Similarly, cli tools are very popular on linux, and it is very easy to bind keys to them. Luckily a lot of tools work on both linux and mac, but this is not always the case. Replicating my global hotkeys has been an annoyance on macOS in some cases because of this. In linux, you have control of and multiple options for basically everything (e.g. bootloader, what you use for networking, what you use for notifications, etc.). In the case of notifications, on linux I can just bind a key to "dunstctl close-all" to close all notifications or "dunstctl history-pop" to show old notifications. My notification daemon is designed with scriptability in mind. If I want to have a similar keybinding on macOS I have to go through an arduous process of trying to find some up-to-date applescript snippet that actually works and isn't slow (couldn't find one that met either requirement) or learn to use some other automation tool. Unlike the WM case, I'm sure it's possible, it's just that macOS is just very clearly not designed with the use-case of keyboard for everything in mind. It can still support it very well, but with linux I can have it so that non-keyboard-friendly software just doesn't exist on my system. I don't need to workaround it.