Hi Simon_Geary | The new Forms experience in Microsoft Lists are native within Lists and do not use or require Microsoft Forms, Power Apps, or Power Automate. All previous integrations still exist, to further configure and customize your lists, for certain scenarios like reaching anonymous audiences, showcasing a number of data sources in one view, and adding rich business logic/flow - respectively.
That all said, a big use case for Microsoft Forms is anonymous submission.
Lists forms are useful for lightweight workflows (scenarios where form responses are further acted upon, like assigning the responses to someone, changing status, adding comments, adding automations etc.).
+ a small FYI, our blog editor, sahilbaid is also working on a new Help article for support.office.com - and taking in feedback like yours and throughout comments here and in this LinkedIn chat + any future ideas rolling into the Lists Feedback Portal.
Thanks for your interest and thoughts, Mark