You absolutely could have a REPL+extras kind of keyboard interface for an aircraft (it would be an interesting project!) but it might not be the best decision for an actual aircraft (actually testing this, how a pilot trained to be an expert in this kind of control would faire in stressful situations would also be an interesting project)
It would probably be a bad idea for a real world aircraft, but designing and testing it would be fun!
This would be frightening but not because I think the REPL itself is a bad idea. However, with a REPL comes -- whether you want it or not -- scripting. Do I want to fly a plane scripted by the pilot? Probably not. Even if they end up creating great scripts, it means they aren't exercising that checklist manually anymore and might be unable to once it's needed!
It would probably be a bad idea for a real world aircraft, but designing and testing it would be fun!