Mailchimp vs Substack
Mailchimp is an email marketing tool with campaigns, automations, and e-commerce. Substack is a writing platform with built-in audience discovery. They serve fundamentally different needs despite both sending emails.
Verdict
Different tools for different goals. Substack if you're a writer who wants to publish and grow an audience with zero setup. Mailchimp if you're a business that needs marketing automations and e-commerce integrations. Most solo creators are better served by Substack (or beehiiv).