Not even remotely. The Elder Scrolls games, for example, would be the gold standard in “open worldiness”. Bloodlines was basically a bunch of Half-Life 2 levels that you could fast-travel between freely, but only after unlocking them through story progress. And sometimes it locked you out of traveling. By being “hub based” it basically means that a section (like Santa Monica for example) was totally separate from other sections (like Chinatown for example). You enter that hub and you basically have a (mostly) self contained little RPG environment. A quest or location may connect off of that hub (like the Ocean House hotel in Santa Monica for instance), but you can’t travel there from Hollywood or anything like that. Knights of the Old Republic is another perfect example of a hub based RPG. That felt a bit more natural though since they were different planets.
A game like Witcher 3 would not be considered hub based. Yes, there are key locations which have quests, but the entire gameworld is connected and open to travel freely. If White Orchard, Vizima, Novigrad, et al had been completely self-contained and you could only travel between them via some means of fast-travel with no world in between, then that would be hub based.