There is a simple, basic step you can take to avoid pixel trackers: stop your email from automatically loading images, since images are where the majority of these pixels hide. You won’t be able to avoid all of the trackers that can hide in your email this way, but you will stop many of them.
Read more:
Krasnoff, B. (2021, June 11). How to stop your emails from being tracked. The Verge. https://www.theverge.com/22288190/email-pixel-trackers-how-to-stop-images-automatic-download
Illustration by Maria Chimishkyan for The Verge.