My vision is kinda similar to yours. I would like to simplify things as much as possible and make most things behind a single button. :)
I do not want to only cover the single server solution. It will cover K8s and Remote Docker Engine as well.
With K8s, you can definitely scale to the sky, Coolify will be just to simplify the building and deployment part. It will be a huge feature, but I love K8s, so it will come soon. I'm sure it won't cover everything in the initial release. I love to work in small iterations and iterate often.
But before K8s, I will integrate Remote Docker Engine. That will make a single Coolify instance to manage several servers and even loadbalance services between those servers. So it will offer a simple HA/DR solution.
About the project shut down, I do not think it will happen soon. I have a daytime job, so I'm not doing for the money. I'm doing for fun! Coding is fun! It's simple. :)
Also, I will improve the contribution guides as well, so it won't rely only on me.