I'm coming from the other side of the equation. I work for a (small-ish, niche) CRM company, and have insisted that all new customers be very explicitly told that they have to set up SPF and DKIM properly during their migration/implementation.
It would be nice to have something to send them to point out "here's where X% of your emails will go to spam if you don't do this, plus you're Y% of an annoyance on our mail server's reputation, too" but there's not any hard data to be found.
I'm coming from the other side of the equation. I work for a (small-ish, niche) CRM company, and have insisted that all new customers be very explicitly told that they have to set up SPF and DKIM properly during their migration/implementation.
It would be nice to have something to send them to point out "here's where X% of your emails will go to spam if you don't do this, plus you're Y% of an annoyance on our mail server's reputation, too" but there's not any hard data to be found.