The culture seems to be that individual departments get to decide their own software, based only on their needs. Interoperability is not on their list.
So radiology buys what they want, admissions buys what they want, and so forth.
Then, the department that has the least clout and direct funding (IT) has to tie it all together.
There are some actual standards like HL7, and some generally accepted non-standards like Orsos, but they are all too loose to solve the problem completely.
Changing a name is hard partially because it is one of the identifiers that tie the mess together.