Templates and email editor
The drag-and-drop editor is sluggish, mobile rendering is inconsistent, and you can't export the templates you built out of the platform.
What people actually say
✕Mailchimp explicitly does not allow exporting drag-and-drop templates as HTML — only custom-coded templates can be exported, so anything built in the visual builder is locked in.
Source: Mailchimp KB, export template HTML ↗✕Reviewers describe inconsistent mobile rendering and layout limitations as common friction points, with extra time needed to adjust formatting across devices and email clients.
Source: Capterra, Mailchimp reviews (login required) ↗✕Exported custom-coded templates ship head and style tags that some email clients strip out, so what looks fine in the preview breaks on send.
Source: McGaw, Mailchimp template HTML export issues ↗
Templates become React Email or MJML components in your own repo — version-controlled, code-reviewed and rendered to inlined HTML by a build step that's been kicked by every serious sender for a decade. Previews run against Litmus or Email on Acid in CI, and you keep the source forever. There's no proprietary block format to escape from.