I moved from Medium to Substack, and except for a few cross-posts, I've never looked back. I never fit in at Medium, where the emphasis seems to be on content and marketing and chasing the elusive golden ring called 'Success'.
It's interesting that you've written an entire piece on Substack without ever experiencing the process.
It's interesting that most of the links you've provided are from writers who talk about marketing and their successes.
At Substack, the only stories I've encountered on marketing and monetary success (including stats) have come from writers who also write at Medium. Nobody else seems to care.
I'm a blogger, but the newsletter format works well for me. I've found my voice there, mainly because of the subscription format. Once I'd built up a good number of subscribers I relaxed. I felt my voice changing along with my attitude.
These were readers who wanted to be there. They wanted to hear more from me and they let me know by subscribing, allowing me into their inboxes whenever a new post was published.
I'm all for community when it comes to writers and writing, but what's refreshing about Substack is there's no room for the constant competition, or the dubious pitches on money and success, which is what finally drove me away from Medium, sad as I was to go.
There is so much good writing there I get lost sometimes and realize I've been reading for hours.
Incidentally, I hadn't planned it this way and didn't really expect it, but I make more money at Substack then I ever did at Medium--which isn't saying much, but it's a perk I can't help feeling good about.
One of my blogs is for writers. It's here, along with a Tutorial for Newbies (see the section below the banner).
https://writereverlasting.substack.com/
Substack isn't for everyone, but if you decide to give it a try there are any number of people willing to help you get started. I'm just one of them.