hashing the binary?
At the very least, you won't be able to protect info like the position of entities and players (You need them even before you see the players to avoid problems, meaning anyone can create a wallhack or an aimbot).
If one could create a trusted environment, that would be a different story. I do think this is possible with cloud gaming. If you can't interact with the game memory, the game files or the underlying operating system, the best you can do should be macro or AI based on what's displayed on the screen.
Raw Autoaim Bot -> Neural Net (since its open source) -> tweak inputs until its considered a human -> send the tweaked autoaimed command.
Are you suggesting that BzFlag sysadmins are going to be custom-training their own neural nets?
Based on my experience with LeelaZero, its far more likely for people to share weights with each other. And participate in community-training. Not everyone has the skill to spin up TensorFlow, carefully partition off training data, and monitor neural nets through training.
But almost anybody can download the "latest weight file" as a Cronjob and update their bzflag server every day or week.
2) Linux distributions compile BZFlag themselves, they don't just distribute upstream's binaries.