What else do you think Gmail means, when they give those recommendations? Using a tracking pixel isn't perfect, but like what peter said in another comment som

What else do you think Gmail means, when they give those recommendations? Using a tracking pixel isn't perfect, but like what peter said in another comment somewhere here, it's the best we've got. If you want to implement Gmail's (and other ISPs) best practices, then you need to do tracking of engagement. Just because you don't like it, does not mean that is not considered best practice. Just because it won't be 100% perfect, does not mean it's not considered best practice. You may disagree that it should happen, but you cannot factually say it is not a best practice.