But as a newsletter publisher they don't share that information with me. If I don't track it myself, eventually my engagement metrics will fall below a certain (undisclosed) level and everything goes to the spam folder.
That is surprising, and unfortunate. I believe this will ultimately have to change. The percentage of people blocking remote content will only go up. I block ALL remote content in my emails, and there is nothing that will convince me to stop doing that.
Can you imagine the comment threads if google was secretly sharing inbox engagement data with marketers?
Anyway, it's been like this for years and the overwhelming majority of email clients load images by default so everyone mostly works around it. I don't think it's changing any time soon.
All it would take is a single default configuration change by Apple, Microsoft, or Google. It is not crazy at all to think that Apple would change the default setting to block loading remote content.
I'm curious how they're doing it. Without having used their product, I gather that they're blocking certain known trackers and/or checking for tracking pixels directly. But it's not hard to put a unique tracking link on any arbitrary image which is part of the email's content. The only full defense is turning off all images.
edit: apparently they automatically cache the images on delivery, which should work. This is really a change that needs to come from the mail providers so good on them. As long as they don't try and assume what the user is interested in like Gmail does, they can drop tracking all they want.