What about the stuff that goes 'clunk'?
From (bitter) experience not all of IT stuff is software related. Or, to be precise, Microsoft software related.
What about getting third party applications to fit into the enterprise system. Stuff like, for example, clever printers, contact management systems and other stuff that firms may use. Because, like it or not, not everyone's business starts and stops with Microsoft Office and [bleedin'] Edge.
These applications need to be integrated. Bespoke applications need to be written and all these have to be done under the watchful eye of a locally based IT department.
Further, when it comes to issues not every issue is software related. Or, to be precise Microsoft software related issues. What about when a router starts to spout noise down a wire? Who is going to track that down and re-route the cabling? What about when a UPS starts to fail, who is going to check that? Who is going to do the off-site back-ups and data storage/destruction? Who, in actual fact, is going to replace the ink cartridges, get the right paper. Who is going to go to regular work-orientated social meetings with similar companies to discuss issues, requirements, vendors and future progression? It's not all going to be upgrade to the latest version of MS Word or Excel as the sole answer.
This, even if it works (in terms of not falling over) is going to restrict advancement and progress in the workplace.
There is not a single upside to this that I can think of.