They can want and they can push. That doesn't mean it's going to happen. There are too many companies and indeed, people who will want tighter control over their data and their processes. Either because of security concerns, real or imagined, or just because they are control freaks. I'm in this group myself. 🙂
So, I don't know if you have a relationship with insiders at Microsoft to be able to answer this question but speculate for a moment. What do you think the likelihood is Microsoft will add capability for ADF to access other cloud providers and integrate seamlessly in an on-premises only environment?
Just learning about Sql Server and other databases since 1998.