[viking2917]

Depends a bit on what you want to accomplish.

I use Jekyll/Minimal Mistakes/Github pages for product blogs, where I just want to broadcast information or have it available for people to find through search, and where I need to own and brand the domain name itself.

I use Substack for a few projects where I want a stronger relationship with the audience - commenting, automatic email list building and distribution, and easy/attractive formatting. I just keep the Substack free, and don't worry about the domain name (x.substack.com) is fine.