Obsidian could be turned into a tool for Semantic Wikis with a yet-to-exist plugin. You could use in-line properties from the Dataview Plug-in and inflate views on the Obsidian Canvas, with links being drawn between notes, and the label on the link being the key of the property.
Hey I sort of built this!
Ontology
A plug-in for managing types and their properties in Obsidian would be cool. It would combine neatly with the semantic canvas plug-in that I am developing. You could use a folder to contain the meta-model with notes that describe each entity whose meta-data describe the schema of the properties associated with that entity Inheritance would be an important feature and would likely require some reserved property keywords. You would need a couple of base classes that all other classes would extend.
Thing