mouse scroll zoom is broken when in pixel preview mode (PC)
I just updated to Illustrator 2019 on a windows 10 PC
Given I have any size project open
And my "zoom to selection" preferences are on or off
When I turn on pixel preview view mode
And I have alt selected
And I use my mouse to zoom in and out
Then zoom chooses a random center point to anchor it's zoom
I have no issues when in "over print preview" mode, or when using my keyboard in "pixel preview" mode.

Please accept my sincere apology for the inconvenience. Please get in touch with us at any of the other support channels – https://helpx.adobe.com/support.html . Since this is not a generic issue that we can reproduce at our end, we will need someone to look into your machine to figure out what is going on here.
-
Wout Standaert commented
I have the same issue, I'm on Illustrator 26.0.1. In Pixel Preview, every zoom level until 100% works well, and then it will drift starting from 200% and up.