It's a difficult uphill battle to get people interested in how things work under the hood, which is what you need in order to know you can do things like easily host your own package repositories.
Yes I can host my packages and write tooling around it to make it easy. But JFrog already has all the tooling around it, and it integrates with current tooling. Why would I write the whole thing again?
> I don't do a ton with Docker outside dev tooling, but I have never understood why private container registries even exist?
You know the options and have made a conscious choice:
> Yes I can host my packages and write tooling around it to make it easy. But JFrog already has all the tooling around it, and it integrates with current tooling. Why would I write the whole thing again?
So presumably you are not the kind of people I was talking about.
EDIT: I'm also assuming by the rent seeking part that the parent is referring to paid hosted services like ECR etc.