We included an improved monospace font with the WYSIWYG composer mode, JetBrains Mono, and you can see this in posts… for example:
⌘ ⇧ .
So we should switch to that for <kbd> tags too to fix this: ⌘ ⇧ .
Another issue is that we have a bit too much space between glyphs, generally the standard on MacOS is to have not quite a full space, as seen in menus throughout the OS: