This feature request might be the same or very similar to this other request.
I would say fix hierarchy might be difficult to be implemented across the whole Anytype because in data processing, linkage can unstoppably expand and might create loop; thus fix hierarchy can be processing heavy and could limit flexibility of contexts and viewing angles (See detailed explanations here about fix hierarchy vs dynamic relation.)
- What you could do is to create pesudo hierarchy
- If toggle for every block is implemented, you use be able to create your own structure in canvas for object display. There is no need for implementation of fix hierarchy between objects.
A different approach to fix hierarchy or preset nesting would be a way to customise or create a (on-demand) static or dynamic representation of hierarchy through relation.
- For example, through object as tag with grouping objects through object/tag in sets, you would be able to group tasks by the criteria from ProjectRelation (object-supported relation) to mimic the upper hierarchy (ProjectObjects), then perhaps group by MainTaskRelation or StatusTag.
- Object Context and Collection-specific relation would enable dynamic representation of objects and/or relations.
- Depth selection might also be useful on graph and can mimic sub-objects.