Content types on one library changing New menu on all libraries in a site

I have a SharePoint Server 2019 farm set up, which is bound to an Office Online Server farm. I do not want the +New menu on document libraries to display the Office documents as the experience of creating a new document in OOS is not the best. I have removed the binding for the edit and editnew actions and that had removed these options from the +New menu as required. 

On one of the libraries on one of my sites I subsequently allowed management of content types and created custom content types. The +New menu displayed the custom content types. However all the other libraries on the site are now showing the Office documents in the +New menu, and selecting any of these of course doesn't create a valid Office document. So changing one library's settings has affected the whole site.  Changing the library settings back to not allowing management of content types does not revert this behaviour - the modified library now also displays the Office documents in the +New menu. This is seen in multiple browsers and in the modern view of the libraries.

Any ideas as what could be going on with this? How can the +New menu behaviour be corrected?

Note this is an on premise environment, not M365.

Edited: on further testing this is difference between the site templates. Removing the OOS bindings for edit and editnew actions on the SharePoint server farm affects the New menu on libraries in a communication site, but not on libraries in a team site. The sequence of events led me to believe it was the content types having this affect. It would still be good to know if there is any way to change the behaviour of the New menu.