To me, it's a pressure release/ROI question.
There are tons of incredibly beneficial computing improvements that it doesn't make sense to spend IT resources on, because there are better ROI opportunities for them to focus on.
But! That doesn't mean the things they can't handle aren't valuable.
My preferred method is (1) require documentation (using a standard template) on all processes implemented by non-IT (what it does, how it does it, what value it delivers to the company, what the fallback manual process is, etc.), (2) store these process docs in a centralized location, which then becomes IT's backlog, and (3) any change control / regulatory requirements.
The grand bargain is then:
- Anyone is authorized to improve processes, if they generate the documentation
- IT has the authority to force decommissioned of an existing solution *after* they've delivered a working replacement
The non-IT staff build those things because they've identified a way for the company to improve itself, but the process for getting what they want from IT is too expensive/onerous, IT has delivered disappointing results too many times, etc. Find a way to meet in the middle, or the non-IT staff are just going to build them in their own shadow cloud account and eventually make the IT department redundant.