Speaking for myself, you've got reliable delivery for the kinds of emails that matter least to users. I really don't care to receive most "transactional" emails

Speaking for myself, you've got reliable delivery for the kinds of emails that matter least to users. I really don't care to receive most "transactional" emails and I definitely don't care about newsletters. Meanwhile, my experience with gmail is that I sometimes miss individual emails from human beings because they got caught in the spam filter. This state of affairs doesn't make email useless, but the system does seem to favor sophisticated bulk senders with tons of resources to devote to the problem over real people just trying to communicate something important.