I have never felt the need to use more, also I mainly navigate with Super + Alt + {Left,Right}
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Though Gnome workspaces are not intended to be used like they are on a tiling window manager; you should just use the workspaces you need and dynamically create them and move apps. Assigning an app to workspace 10 that just stays there all day until you need it ist not the intended workflow.
You are aware that Manjaro ships a heavily modified version of Gnome (lots of theming-stuff and extensions)? You should try vanilla Gnome (eg. on Fedora/Arch/VanillaOS) or try disabling everything.