It does if you're not paying for it. There are plenty of companies that will gladly handle the packaging, assure all the interdependencies work well together, and even support the effort. They also do release management, ensuring that everything is on the most recent version that all works together. That has a cost. You can either pay someone to handle that work for you (smart - you and many other companies are sharing that cost) or you can do that work yourself (not so smart - now you shoulder all the costs).
Just as an example, consider Hadoop and its ecosystem. Another example is Elasticsearch. There's work involved in making these platforms production-ready and keeping them and their dependencies up-to-date and ensuring all your applications in your portfolio are using the same set of software. Most organizations are not prepared to take that on. So they turn to a vendor who will do it for them for much cheaper than they could do it themselves.
That's why the saying is "free as in freedom, not free as in beer" because open source software is not free as in beer. At least not when factoring in the total costs.
> Open source clearly does not mean packaging your own software.
The packaging argument was made in the context of complying with software licenses. Responsible companies which perform due diligence on the software they run have to track the provenance of all software that ships as part of their dependency closure. If you want to ensure you're not vulnerable to lawsuits then you can't simply apt-get stuff from a PPA. You need to build it yourself, and track exactly what goes into that build.
Meanwhile, if you opt to run managed service from a cloud provider, you don't have to bother with that because that's not your problem (or liability) anymore.
> But that should apply to all readily available container images on docker hub as well, right?
Yes, and it does indeed apply to all readily available container images.
In fact, it applies to any and all software packages put together by third-parties.
I mean, who in their right mind downloads random stuff from the internet and expects to just drop it in production software which you build your business upon?