I'd ask them for a reference to where that's stated by Microsoft.
I would find it incredibly unlikely. Too many people use Excel to connect to too many SQL sources, including SQL Server.
My guess is that they are looking to implement some other change and that might block the use from Excel. OR they just don't want people connecting to the databases from Excel. But that should be fixed by permissions if required.
I don't think you'll find anything on the Microsoft website saying that, as I don't think it's true in the first place.
The Learn content pages that show you how to do this, say nothing about there being a move to remove it.