Those scenes never show the person using the mouse!
YOU NEED TO USE THE MOUSE TO PROGRAM OR ANYTHING ON A COMPUTER
Actually, most systems (if not necessarily most applications) can be used without mouse, even if it's not necessarily efficient.
But more importantly, command-line interfaces are largely operated with keyboards, and it's not unimaginable for them to use these instead of graphical user interfaces for hacking.
And even if something has some form of GUI - like Visual Studio Code - lots of things can be done faster with keyboard rather than a mouse (e.g. going to a specific file with Ctrl+P shortcut and typing out part of the filename vs scrolling through the file explorer tree and clicking the right entry).
So yeah, having a hacker primarily/exclusively use keyboard is not that unrealistic, since a well-learned keyboard input is more efficient than mouse. That, or maybe someone just opens a program to run through the database of hashed passwords and trying to find matches and leaving while the task executes in the background, I dunno.