Microsoft just published that from the 5th of August, the exam will be updated and new skills are being added. Also, some of the old skills are being left out. I'm thinking language packs and migrating user data. I'm not seeing it being tested now with the exam.
Still a valuable skill, you think? First thing that comes to mind is that migrating user data is pretty much straight forward with OneDrive. At least, that's how I feel at work helping users. 
Microsoft is focusing the exam objectives on the latest technologies. With the move to desktop as a service, there are different solutions for managing user data (FSLogix for example). Also, as you pointed out, many organizations take advantage of OneDrive and Microsoft 365, and rely less and less on locally stored data.
That doesn't mean things like USMT are unimportant, it just depends on the environment you are in.
Mike Rodrick
Edutainer, ITProTV
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