I came here to say this too. I’m really not sure he’d leave his very public personal email in there in purpose. I am not ashamed to say I still use my personal Gmail for testing in 2025.
By the way, this is not specific to MCP, could have happened to any package.
I maintain the Nodemailer library. Several years ago I used my personal email in a few usage examples. Developers still copy that old snippet, add their SMTP credentials and send test emails - which land in my inbox.