I don’t think the shape or functionality of the mouse has changed much since the original version that took AAs, so I honestly wouldn’t be surprised if this isn’t even designers being snooty and it’s just Apple not wanting to retool their manufacturing to accommodate a front charging port.
The USB-C version they currently have for $80 on their website has the port on the bottom, yes.
https://www.apple.com/shop/product/mxk53am/a/magic-mouse-usb‑c-white-multi-touch-surface
I don’t think the shape or functionality of the mouse has changed much since the original version that took AAs, so I honestly wouldn’t be surprised if this isn’t even designers being snooty and it’s just Apple not wanting to retool their manufacturing to accommodate a front charging port.