Neo4J is still a relational database. […] Relationships are also first-class citizens in graph databases, and in some cases are your focus.
Many are confusing the relational model for relationships between entities. In the paper “A Relational Model of Data for Large Shared Data Banks”, E.F.Codd writes:
The term relation is used here in its accepted mathematical sense. Given sets S1, , … , Sn, (not necessarily distinct), R is a relation on these n sets if it is a set of n-tuples each of which has its first element from S1, its second element from S2, and so on.’ […] More concisely, R is a subset of the Cartesian product S1
Codd’s paper is only 11 pages long, so if you haven’t checked it in a while, maybe it is time to do so.
The relational view (or model) of data described in Section 1 appears to be superior in several respects to the graph or network model presently in vogue for non-inferential systems.
This was written in 1970 and things are changing again.