That's by design. They want to minimize the number of people who completely unsubscribe.

Having an Unsubscribe All Lists checkbox doesn't minimize that. It just adds form noise and pointless work for a dev. The minimization already happens with the preceding checkboxes to select each list to unsubscribe from, but that's just as inherent to the form as the desirable feature of being able to keep certain subscriptions while unsubscribing from others in an efficient way.

A button or link in place of the 'All' checkbox makes sense and is easiest for users to understand, and has less user actions required.

Treat your customers well even when they're exiting (especially) so they remember something good next time they consider you. "Well at least they made it easy to unsubscribe" is better than "Well they made it unnecessarily complicated to unsubscribe". No need to add insult to injury.

I think this is about confusing AI like that offered from gmail or iCloud email that will unsubscribe for you if you click on unsubscribe from their respective inbox / application. Fastmail offers this too.

I noticed there are times I have to do it manually and can't take advantage of auto unsubscribe because the button layouts are like this.

The unsubscribe buttons in email clients are powered by a header that the email includes. Google and Yahoo just started requiring these for all bulk senders (they were previously a best practice only). It doesn’t rely on what the manual preferences page looks like.

This is just a standard unsubscribe header. It's added by the sender specifically for this purpose and has nothing to do with the UI you see. Not everything is AI, but it being the default assumption is funny to me.

I have to admit I've never experienced this. When I check the "all" checkbox it goes and checks all the other checkboxen for me. Maybe I've only interacted with "nice" unsubscribe pages.

I've seen both versions, and whether they check or uncheck all of the other options (behaving like a radio button), both versions are overcomplicated nonsense.

The unsubcribe-all should just be a link or button with its own submit value or URL param (like unsubscribe=all).

I don't know why people overcomplicate things.

It makes no sense to have a checkbox for "Unsubscribe All Lists". That should just be a link. There's no point in adding a redundant form element even if it's only conditionally redundant.

Or a radio button between all and choose which to unsubscribe from.

I remember when I designed a list of checkboxes this case was specifically considered. The last one needs to be updated when all of the checkboxes above are checked or one of them is unchecked.