In this context: Generative ML models allow e.g. a single motivated writer with almost no budget to make a Visual Novel which they then could publish on Steam (before the policy change) for the world to see.

Write the script yourself, generate and curate 2D art assets, optionally generate and curate your OST / BGM, optionally generate and curate voice lines, put everything into Ren'Py. Done.

It's still very much not easy if you do not want to make shovelware, but it's possible now for a sole developer (or very small team) with no great artistic and musical talent.