I'm always in favor of repairability. Built-in lithium batteries are actually a bit troubling and generally I'd prefer AAs or AAAs so I can use rechargable -- or at the very least a modular battery that can be serviced later on.Mine cost $199 (US) when I ordered it with my ac Studio M1 Max. Based on my online research the battery is not replaceable when it gives up the ghost. Does anyone know if that’s the case. If so it’s another argument for right to repair.
For what it's worth, though, you can also use it as a wired keyboard by plugging in a Lightning cable. I assume that still would work with a dead battery?