At scales far below what you're talking about people experience grave difficulties making sense of big graphs.
https://cambridge-intelligence.com/how-to-fix-hairballs/
One of my favorite examples is this guy
https://en.wikipedia.org/wiki/Mark_Lombardi
I saw an art exhibit that showed some of the sketches that he made and it was clear that he worked really hard drawing and redrawing each graph and they went from being hairballish to telling a clear story.
You're also very insightful to be talking about the specific scale you're working at because it matters. Graph workloads can drive you batty because they frequently defeat caches by beating very nonlocal.
For your small data set you are in the range where you can get a "big" computer with say 64GB or 128GB of RAM and be able to work in RAM. You might be a little disappointed with the performance (it takes a while to touch every memory address in a 128GB machine) but it will good enough if you're efficient and disciplined.
As an RDF fanatic I'll share that I have handled data sets on the small end of your scale with
https://virtuoso.openlinksw.com/
