The problem with that is that the backtick key is awkwardly-placed on most (all?) non-US layouts. In the UK, for instance, it's immediately above the option ke

The problem with that is that the backtick key is awkwardly-placed on most (all?) non-US layouts. In the UK, for instance, it's immediately above the option key so to hit it requires clawing together your thumb and little finger. It's surprisingly awkward to switch between that and Cmd+Tab. GNOME does this much better - window switching is done using Super+<whatever the key above Tab is>. In the US, that remains ` but elsewhere it's so much better than on MacOS.