Why can't we redefine words? Words are created, generalized and redefined all the time in English. Is it incorrect to say "he stole my idea" because I still hav

Why can't we redefine words? Words are created, generalized and redefined all the time in English. Is it incorrect to say "he stole my idea" because I still have the idea? Maybe at one point this wording was incorrect, but not anymore. As content gets more digitized wouldn't it make sense that to steal be generalized to mean copy/take something without permission instead of just take, especially considering it has already evolved to mean "take credit for something without permission" along with "take without permission"?