Microsoft basically does the same with internal Azure services? When I was there our budget/usage was based on and consumed at the consumer price for GPUs and other compute. What happened behind the scenes really I have no knowledge.

Not true. Azure has a very different internal pricing. You can often get a glimpse of it if you have a.. particularly enterprising TAM. What happens sometimes (Like now when compute/GPUs are in high demand) is finance department would calculate the opportunity cost on allocating those resources internally vs selling them externally. The calculation isn't even always straight forward. What is the opportunity cost of using compute for internal CI or company operations vs selling them externally? It's not a straightforward equation and you would have to adjust the scale often depending on how clogged your internal processes get.

The extremely discounted internal cost promote waste, so there is always a room for improving efficiency, but that too has a cost.