I would like to be able to pull for changes, or be notified of changes, in a Sharepoint list, which is not associated with a drive. This is a list of pure metadata stored in the columns/fields, so a change would be any new items, or changes to the field values of existing items in the list.
I am aware of the Graph API /delta route, but this appears only available on drives.
By the looks of it, I have to use the Sharepoint API directly (https://learn.microsoft.com/en-us/sharepoint/dev/sp-add-ins/synchronize-sharepoint-items-using-the-rest-service). Is that right, or is there a way with Graph API?
Yes, there is no support yet for sharepoint delta queries according to this document. You can raise a feature request in the Microsoft Graph Feedback forum so that the Product team may develop it in the future.