Any idea how to fix this without removing Mathematical Operators from the ranges in Glyphs?
There is a
unicodeRanges custom parameter in the font tab.
Yes, that is what I am using and is quite handy.
On the other hand will removing these Mathematical Operators cause any issues with the functionality of the font?
It might prevent someone to use the font in some math apps. But as you font probably only has very basic math support that would not be a big problem.
Yes. Pretty basic math support.