SarahBaker: I'm sorry to hear you're having trouble playing because of this! We've noticed the desire for custom key bindings and we're taking it into consideration. I cannot, however, promise it will be added at this time.
I hope you'll still be able to enjoy the game without!
-Dev
So, apparently the "consideration" didn't lead to action. I second any comments that exposed this as simply ridiculous: A game without remappable keys in 2019-2022!
Although I'm right-handed, I'm using the mouse with my left hand, because I prefer the symmetry of the numpad for my key controls.
So, no, I won't be able to enjoy your game. And I refuse to fix your negligence with any third-party tool. No rebinding for us, no money for you. Lose-lose. :-(
edit: I also refuse to edit config files just because you are too lazy and/or ignorant to your player's desires. It's a matter of principle: My money goes to devs that don't behave this way.