I just want them to support Ctrl+Backspace to wipe the contents of a cell...
Compact and laptop keyboards; sometimes excluded, often poorly/inconsistently sized/positioned.
There's a much better chance of Ctrl+Backspace being a consistent movement independent of keyboard layout, so I can appreciate where the parent is coming from.
I'm not saying there aren't scenarios where ctrl + backspace would be useful, however the majority of the time I'd argue that delete is available and should be used.
Is the desire for a ctrl + backspace chord coming from some other system where this is the standard keying?
It's very common in IDE's, even FireFox supports it if you type words in the address bar, press Control Backspace and the behavior happens there.
Asking ChatGPT about the origins of this, it points to Control+W originating from Unix Terminals, and how it's been adopted by most IDE's as Control+Backspace.
Microsoft has very poor support for it in their tools, and I use MS products for the bulk of my work.
Moving to non-Microsoft products like Google Sheets, and viola, Control+Backspace works.
Even muscle memory stuff like Control+Shift and left arrow to select previous words; also not supported by Excel, but it is by Google Sheets and IDE's.
Those are the ones I use most frequently and these keystrokes are now deeply embedded in my muscle memory.
BTW, I would take slight issue with your expectations of what a human might expect... I actually think the standard CTRL+V paste does what 90% of Excel users expect.
[Edited to add: this is on Windows, didn't read your comment properly about your experience on a Mac. My apologies.]