I've started receiving emails that say 'reply "unsubscribe" to stop receiving emails' rather than have an unsubscribe link. This just started happening a few mo

I've started receiving emails that say 'reply "unsubscribe" to stop receiving emails' rather than have an unsubscribe link. This just started happening a few months ago, so I think this is a workaround that someone figured out. I've started blocking all of them and sending straight to spam.