Sendgrid customer here. Since many services rely on SMTP providers like Sendgrid, they should have a way to notify customers when their server go down and transactional notifications may be disrupted. I shouldn't be notified by someone who know we're using Sendgrid and happen to read HN.
Also seems like best practice would be to have SPF/etc. entries in place for multiple ESPs, even if you routinely just use one, and be able to switch, for just this reason.