Blogging on Substack vs personal website

I'm not a web developer, but I'm comfortable enough with HTML that I can write a static website, and keep the blog under https://username.com/blog/ – hosting is free, and the domain name is a negligible sunk cost.

I also do not plan to charge for access or write very regularly. What I want is to reach the biggest audience when I do write something.

So I'm wondering about the remaining pros and cons of blogging on Substack vs a personal website.

I know that Substack allows users to subscribe. But with a static site, I can just ask the readers to follow me on X so that they won't miss future posts?

And if they want to discuss my post, let them tweet at me – that helps the post spread, right?.