Usually the issue is that on-prem is seen as legacy and gets legacy budget and talent. Bigger companies are going to stick to a couple of big providers who don’t sell/rent iron.

My employer adopted cloud as a business/financial play, not a religious one. We often land new builds in the cloud and migrate to a data center if appropriate later.

The apps on-prem cost about 40% less. Apps that are more cost effective in cloud stay there.