Riding even a big cruiser or touring bike like a Goldwing on gravel isn't the end of the world, it's all in understanding that despite behaving differently, it's not necessarily inherently unsafe so long as you have an appreciation for the different behaviours, and the different way you need to ride to manage them.
I have ridden my VTX at 80KPH down gravel roads without a care in the world since I trust my bike and I know it's not going to do anything stupid unless I do something stupid to begin with. Yes, there's different levels of gravel, and if you get into a really loose mixture (IE, fresh construction zone pea gravel type crap) you need to manage that differently versus a packed gravel road that you'd traditionally see under normal conditions, but again, you manage that as it's thrown at you.
I know a lot of riders (especially in the touring/cruiser crowd) can be scared (or even mortified) of riding in gravel, but like anything, it's a learned skill with a comfort level that can take some time to build. There are also some who are terrified that the gravel will kick up and scratch or damage their bike, which is a legitimate concern I suppose, but in my case...I don't care much - my bike is for my enjoyment, I'm not saving it for the next person, nor am I worried that a might get a little pit in the paint on a fender or something.
Speaking of the whole "off roading" thing reminds me of bit of a crazy trip I took with a buddy in 2017, chasing listings in the "150 unusual things to see in Ontario" book. Rode basically 5000KM in 4 days and saw a ton of wild and cool stuff, but this "road" we rode down in a little town called Larder Lake (heading to a listing called "Ontarios Stonehenge" sticks in my memory. This is an actual photo of what we rode through.
Now, the washouts and such were at the absolute limit of what my bike could physically manage as I was bottoming out and such...but we got it done. And my buddy was on a decked out Indian Chief, but like myself, he's not afraid of an adventure.
Not far past this spot the road got too poor for our bikes - would have really needed an ADV at that point as we were talking several foot drops and pure loose sand and such. We ended up parking (we knew when to draw the line) and walked the last half K or so to the actual destination for our photos.
