One of my playtesters is better than me at the game and top of all the leaderboards, please help me humble him.

1 day
This has nothing to do with piracy. Rewind the clock 20 years and doom’s source code release meant even more than AI code de-obfuscation. The art and assets are still copyrighted. The ability for people to port doom to everything under the sun has meant more sales of the game, not less.
If every gamedev in the world released their source code tomorrow, no one would lose out on any sales, but the public sure would benefit from ports and mods etc.
The only thing that might get lost is microtransaction locked cosmetic bullshit, which frankly needs to die anyway. But even that wouldn’t get lost necessarily because of authoritative servers and terms of service.

Can we please just skip the middle-man and start open sourcing everything instead of burning all the world’s resources to achieve the same goal?