Haven’t read the paper yet, but a great list of authors! I have worked on Knowledge Graphs at two companies, and I am fairly opinionated about them. I think that large fast KGs (i.e., no OWL reasoning) are a good tool for organizing different data sources, but I have lost my interest in KGs for Knowledge Representation (in the AI sense). Just a personal opinion, lots of people in the field would disagree with me.