If you have declared “Substack bankruptcy” because you subscribe to too many newsletters and never get around to reading them, using RSS readers (I like and use reeder) is one option. Check out https://yakread.com. While looking at the front page it comes across as a place that will recommend you newsletters to read, it performs an even more import function - you get your own email address like <youremail> at yakread.com that you can use to subsccribe to newsletters, and read them on the website, bookmark them, etc.. You can send yourself emails from your regular accounts, that might allow you use this as a private blog, and also save articles that were not from a blog.
The web interface is pleasant, focussed on rendering articles in a reader friendly format, and quick access to “Subscriptions”, “Read later”, and “Favorites”.
I use their ad-supported plan, which is quite unobtrusive (I don’t remember the last ad I saw there), but they also have a $60/yr subscription.
I came across Yakread because I read a few blogposts by it’s creator Jacob O’Bryant around Biff Clojure web framework.