I am quite annoyed by this layout and the disproportions between the elements of the interface. I think Windows 10 is responsible for some of that, but not sure to what extent. Can anything be done?
There us a long discussion for a similar issue for win8 which is probably related Icons are too small in ArcMap Windows 8
there are several possible solutions towards the end... Dec 2016 or Jan 2017. I would see if any of that will work for you.
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