An ERP system in...LISP? None of the reasons given as to why that would be a good idea are really very convincing or specific to LISP?

The main things you want for ERP are just to simplify database interactions as far as possible and to give you as many and as customizable options as possible for data visualization and curating information for a non techie user. I dont really get why LISP?

Because, with few exceptions, most coding is plumbing. And LISP is the most hackable PVC tube.