I think the solution to this is a bunch of pluggable tools that integrate well. "AI Platforms" do everything, but they do each thing not very well and force you into a particular way of working. (There is a reason we don't use "software platforms" any longer.)

But unfortunately, as you say, most of the pluggable tools are not very good and/or not mature enough.

Here's our attempt at model storage, experiment tracking, and software heritage: https://replicate.ai/

For interactive dev environments, Colab, Deepnote, and Streamlit are all great.

For deploying to production, Cortex mentioned in the post is great.

All are a work in progress, but I think we'll soon have a really powerful ecosystem of tools.