Keyword in this debate is "well-architected" and "most" typically cases.
Now we've reached the scrum argument tactic, if the RDBMS can't do what you need: "it's not the RDBMS", it's, "you're doing it wrong".
Sure you can incorporate a lot of the advantages of a graph db into a rdbms, but having it retain purity/usability of a normal row/col is hard. OracleText comes to mind back in the day. Most architects know a good schema is hard, complex. Graph dbs just make it easier. But yes if done right, schema/rdbms can be blazingly fast.
Biting the hand that feeds IT
