I don't trust third-party platforms.
I have a website with the domain name vnalexander.com. I don’t know why I would promote my work here rather than there. One day Substack will start suppressing some content and promoting other content. And hundreds of good writers will have to somehow or other move their audience from the Substack address to the next “safe” platform.
Instead Reader, you can subscribe to any writer’s website. You can comment on their websites and interact with their readers too. That’s the best option.
Remember the old Internet back in the early 2000s. There was a lot more free horizontal communication then. And not as much surveillance.