If that's true in a large organization, how do SaaS companies actually make a profit?
If you develop an in-house tool, you have very predictable user numbers so you can go on-prem versus cloud for the compute and save ~10x on that side.
You also have the benefit of being second, the other guys already did the hard work of UX research etc. and your in-house team just needs to replicate a slightly complicated CRUD app.
The one significant roadblock I can see is being able to put together the right team for the job. But cost-wise it has to be a no-brainer that in-house is cheaper.