For me, it happens most often when I have a call open in a browser in one window, and a terminal open on the other half of the screen taking notes, and then switch to the call and start typing something in the chat.

I'd say Ctrl+W is just a terrible shortcut for closing a tab.

It's right near Ctrl+Q, which usually quits an application.

While Q is mnemonic, W is not.

It's too ergonomic and requires very little wrist movement for such a destructive action.

I understand your pain, but I blame the author of this weird convention for the "close tab" action, whoever they are