I've been using EmailOctopus to add an email list to my blog. It's pretty good! That said there's no monetization option so perhaps it's not a Substack alternative after all.

I'll get my coat :)

Tldr: substack takes 10% and you can use Ghost either self host or a more sane on premise pricing (for now)

If I was going to do a newsletter (for people too ignorant or lazy to use RSS feeds), I’d probably go with Buttondown and charge the punters $10/year.

Buttondown charges a flat fee based on subscriber count and they aren’t a Nazi bar backed by venture capital.