If I start calling dogs “cats” tomorrow, am I wrong?
If your audience knows what you mean? No. If your audience has no idea what you mean? Yes.
Or have I just taken the first steps towards making my mark on the English language?
If it becomes a norm? Yes.
But what does this have to do with the price of tea in China? We were talking about literally, and how it is literally (the way you mean it) a contranym now. Using it to only mean figuratively (the way you want it to be used), especially when it had been used that way for a long time and even has a history of using is no longer "idiotic" it's just a common usage of the term. It mildly irks me too, however, I can't remember the last time I was actually confused by the intent of the speaker.
You act like humans never fuck this up either.