[alloyed]

The concern here is revenge-spam: someone takes your email and submits it to every mailchimp default form they can find automatically, and then your inbox is flooded with ostensibly legitimate email that you have to manually unsubscribe from, for each individual list.

[notahacker]

I understand the concern on an individual level as expressed in the article, but doubt "revenge spam" even moves the needle with mail providers' decisions on MailChimp mails get through or not, which is the primary concern of people worrying about its deliverability.