I've used Heroku for over 7 years. Heroku's selling point is essentially devops-as-a-service. That's why they can get away with charging so much compared to the hosting competition. A "self-hostable Heroku" doesn't make sense, at least to me. With this, I'd have to do devops, like every other hosting platform. Granted, I did only scan the home page, so perhaps I'm missing something.
Something like this would be pretty handy in an org where I need to run my own servers for various reasons (e.g. I need to be on-prem, or pretending to be on-prem via some VPN connection to AWS or something) and still want devs to be able to have a Heroku-like deployment experience.
This seems like the sweet spot to me. Often times there are smaller internal services which need to be hosted and at a small to medium sized org there's a good chance there won't be proper budget allocated for devops, k8s and the likes. Would be much easier for said org to pay a few hundred (few thousand?) a year and not worry about it. Or make it free and bill them for support when they want to scale up... A bit easier to charge money when the customer is making money in the process.
Think about it this way. Let’s say you’re a company with 500 engineers. Heroku is still a fantastic abstraction to provide to product teams, but the economics may make sense to have a 5-person team owning and maintaining that infrastructure over paying Heroku to do it. This makes even more sense if you’ve got your own data centers and need data locality.
