That doesn't solve the problem; email trackers could just use a unique URL per email.
I'd love to meet these people. I've yet to have a good email publisher experience. whether it's a fortune 500 co or the newest startup they all terribly abuse email.
> unsubscribing you automatically
What is this magic? I've never once been automatically unsubscribed from anything.
That does not remotely sound like the behaviour of responsible "email publishers". Responsible behaviour is to only email people who asked for it, and to stop when they tell you to stop. Clever trickery to spy on people is not the behaviour of responsible people.
If their intention was as you say, it would be really stupid and unreliable trickery, not just because some systems might load the images without the user reading the email, but also because the user might read the email without loading the images. And even if they were to only and reliably load on reading, reading the email does not in any way imply that the user wants to receive it. Lots of people open email before throwing it away. Some mail readers show a preview which may be enough to read the message. Does that count as reading or not?
No responsible organisation would rely on this kind of trickery, and no organisation that relies on this can be considered responsible in their handling of email.
No, they don't.
> Gmail causing a lot of bogus engagement would make it look like people can’t get enough of your content
For a few days, perhaps. Gmail accounts for a significant proportion of all email. 'Publishers' would quickly realise they are no longer able to track emails sent to Gmail. To fail to do so would be their loss; if that weren't the case, they wouldn't bother with tracking at all.