As an IT-guy I can just welcome this decision.
Running an old outdated OS is risky anyway. And if you don’t change OS now it will be even harder the longer you wait (most probably you will only change when there is something not working for you anymore). Much better to do the change now, you can plan it without stress, you have to do it nevertheless.
Plus WIN10 has a way better performance than WIN7 anyway. Did not want to change OS as well when WIN10 came out. I always waited 2-3 years after each release and did the change then, this way you are sure you wont have any bigger bugs at the beginning.
This way Steinberg can focus on the really important things, like fixing bugs and new features, instead of checking everything on the last 3 outdated OS. Most people don’t have any clue at all how time consuming that is.