I just used the NEW admin centre to create a new site collection with the option to have no connection to an Office 365 group. The home page is modern. The document library is modern. But when I open the Site contents page, it shows in classic experience, with the big tiles for lists and libraries.
And how can I change that? In SharePoint Admin, the setting for List and Libraries to default to modern has disappeared.
Where can I set ALL the pages of the site to modern experience?