THE CODE IS THAT LAYER.

If your code does a shit job of capturing the requirements, no amount of markdown will improve your predicament until the code itself is concise enough to be a spec.

Of course you're free to ignore this advice. Lots of the world's code is spaghetti code. You're free to go that direction and reap the reward. Just don't expect to reach any further than mediocrity before your house of cards comes tumbling down, because it turns out "you don't need strong foundations to build tall things anymore" is just abjectly untrue