This project is so bad, anyone with basic physics and electronics understanding can tell it's bad. Unlike @sleepybrett I never even built a keyboard in my life and yet can I still find numerous problems with that keyboard. And I didn't even get to the MCU firmware part. I can only imagine how bad that is.
If this project was done only to learn, then why is it here? People don't usually brag about what they learn. (Look ma! I put 3 lego bricks together.) I mean, it's perfectly OK to build projects to learn, make mistakes and learn from those too - I wish I had time to do that myself - but showing it on HN as if it's some viable product? Don't do that.
Why are you defending it? Just because it looks "cool"?
Let me remind you that you literally opened up with various constructive criticisms, providing value to OP and to others reading. That alone made the OP’s post worth it. Nobody made any claims that it was a product btw, you made that assumption yourself. OP could have—and should have—explained what they were aiming for here, but “Show HN” is literally for things people make, just because some people use it as free advertising doesn’t mean hacking away at personal projects is wrong, in fact it’s the opposite.
As for why I’m defending it? Because I want to, it’s that simple. I don’t need a complex explanation to defend it or myself, particularly when I made my thoughts clear earlier. What about you? Why do you feel the need to shield sleepybrett from criticism while he’s posturing over making a simple keyboard? Why do you feel the need to tear this project down over aspects you haven’t even looked at?
Because it looks to me like some sort of hype product launch / vaporware / investor bait / star farming, or some other foul play, and everyone here gave votes and supportive comments instead of realizing just how bad it must be in reality.