I'll try it in the name of science, but I've never encountered this. What is your use case? In the 13 years I've been using Wacom stylii on phones and E-ink devices, I've never encountered this.

Put on a 3rd party wallet style case with magnet that keeps it closed. Parts of the screen near the magnet stop responding to spen for a time.

Just tested on Note 8. Put magnet on the back of phone and area about 10 times the size of the magnet stops working with s-pen