In SharePoint, workflow can be associated with content types, but Flow does not have such parameter. So my suggestion is that you could use workflow to achieve your requirement so far.
Associate a workflow with a content type when you want to make that workflow available when that content type is being used. For example, a purchase order content type could require approval by a manager before the transaction can be completed. To make sure that the Approval workflow is always available when a purchase order is initiated, create a Purchase Order content type and associate the Approval workflow with it. Then add the Purchase Order content type to any document libraries in which purchase orders will be stored.
For more detailed information about content types and workflows in SharePoint, please refer to:
Meanwhile, you could also submit your feedback to the following forum:
Unfortunately workflows require to have SP-Designer enabled which has been switched off in my organization.
From my point of view it's not quite clear what the long term focus of Flow is...
Will it once be able to replace SP workflows?
Clarifying the scope of Flow would be very good.
When should I create a workflow, when a Flow.
Or will the scope of Flow develop by the input of this community?
Although Flow does not have the content type parameter, shouldn't it still use the default content type of the library where it is being created?
In my case, the file created is corrupted. Is there a way to create a file - without adding content to the file (maybe that would prevent corruption). In that case, I could update the file properties instead (if that is possible).