It’s tough to protect your digital privacy with the modern web but I try my best. One of the tricks I’ve been using is to disable all images and avoid clicking any links that don’t go directly to the desired location. The reason for disabling images is that it prevents your opening of the email from being tracked since the image request (which contains some unique identifier) does not get made. The reason for not clicking on any of the links is similar - they’re rarely the final page you’re trying to get to but instead go through an intermediary that’s able to track your click. You can identify these by hovering over the link and seeing what the destination actually shows in the status bar. If it’s the page you want, great, otherwise I’ll go to the desired page directly or do an incognito search to get where I need to go.
The flow is slower but reducing tracking is important to me and I’m willing to take a bit of friction to give myself the illusion of privacy. It’s not perfect and I’m still being tracked in a variety of ways but it’s one small way of fighting back.