I just finished building up a dedicated gravel bike after breaking a rear wheel on my road bike while riding on a seasonal use road that was gravel/dirt/exposed shale.
My motivation for riding more and more gravel was really just exploration, and the desire to ride new routes and places. Over the past several years I would frequently do rides where I'd just see a road and turn onto it, then another, then another. On weekends in particular these rides led out into the countryside (intentionally away from the routes I commute), and inevitably would include some gravel. Then more gravel, and then instead of just randomly hitting gravel I was seeking it out, putting together routes that intentionally went further afield.
Incorporating more dirt and gravel roads usually means new sights, less distance but probably more hills, and certainly fewer cars. But not feeling safe in traffic wasn't my motivation for riding more gravel - it was really just "hey, that "road" looks fun."
BTW, here's the new bike, and the broken wheel that finally made me decide to build a dedicated gravel bike. My road bike is a triple so going to a 1x11 I was a bit concerned I'd hate it. So far I have one good ride on it and while I notice the big gearing jumps, for the most part they don't bother me. Where you really feel it is riding pretty hard on flat pavement. On the dirt, or on hillier terrain, not so much.
ETA: after this picture (and after my initial ride) I moved the seat a bit higher, and repositioned the shift/brake levers because they were too low on the bar.
