Based on my experience, I would agree with the last point in this article and with knowledge:

“… the divide between ontology and knowledge graph has nothing to do with size or semantics, but rather the very nature of the data. …” Etc.

There tends to be a difference in size between ontologies and knowledge graphs, but that is a by-product of the nature of the data, i.e. the amount of structure, just as size tends to be different between SQL and No-SQL databases as a by-product of the scalability you get by removing logical constraints. The connotation I hear in the word ontology includes more structure than a knowledge graph which allows for more deductive inference and reasoning, which in turn tends to make them less scalable.

As with everything, there is a trade-off that must be set based on use-cases. We should not turn this into an argument about which is better. They each are better for different purposes.