Cut wires in cargo area, driver's side

[Masospaghetti]

I'm almost certain this is from the previous owner's radio install (an aftermarket Sony single-din unit). Should I be concerned? They at least used insulated crimp connectors but this looks like a hack job to me. What was originally installed back here? Eventually I'd like to install a double-din unit in here. I wouldn't mind the factory nav unit but I've heard that can be really difficult to do.