This setting isn't available in the symbol editor, we will log it internally so that the option is added in a future release.
Why in VX.2.1 this kind of zoom has been implemented? The user is forced to work with this feaure that is quite annoying. In VX.2 there wasn't this feature.
The assumption is that if you are selecting pins in the pins window then you are interested in seeing the details of the pin. The lack of setting is just an oversight.