M2 Mac Mini '23 crashes when trying to do a Time Machine backups over smb to a 2014 MacBook Pro. Network issues or Apple Silicon vs. Intel issues?

I have an old 2014 Macbook Pro (Big Sur) that I'm using as a makeshift home server. My main workstation is a 2023 M2 Mac Mini (Sequoia). I recently set up Time Machine to back up over my local home network via SMB (over wifi) to an external hard drive attached to the Macbook Pro. For the most part, it seems to work fine. However, whenever it tries to backup over night or when I'm away from the Mac Mini for extended periods, the Mac Mini crashes and restarts. I've removed Time Machine backups over network from my Mac Mini and that stopped it's intermittent crashes, suggesting that the crashes are related to the network Time Machine backups. Quick search online suggests that this could be: network issues; compatibility issues with apple silicon and intel chips; or even obsolete OS's. Anybody running a similar set up using their old macOS machines as home servers with newer machines? And have you been encountering similar issues with running time machine back ups over SMB? I've also thought about running a Linux distro on the Macbook Pro and trying to set up Time Machine there but I do like having the share screen function to maintain the Macbook Pro from my Mac Mini.