On the forum looks like there are a lot of people who actually take what ever they have off road. As a % of drivers, we are probably under 5% even if you count the people who by profession go there, like guys working for the forest service, or maybe some geological survey guys, NGO's working out in remote areas etc...
Really that's the percentage you think offroad worldwide ?
Aside from overlanding there is real offroading, rock crawling, rock bouncing, rock racing,, desert racing, hill climbing, rally racing, winch racing, mud bogging, arena racing, and many more I can't think of at the moment.
Just because you don't do it doesn't mean that others don't. Taking a self survey from the internet is no way to gauge how many people use 4x4s for their intended purposes, unless your at every one these events and can do a head count on 4x4s being used vs how many 4x4s are in the world your numbers will forever be wrong. And I'm not talking about the folks that take an awd down some forrest rd aka a dirt or rock road take pictures then claim they can offroad like the big boys.
Go call a driveshaft shop and ask why and how they stay in business, answer is 4x4s offroading, drag racers, and jackasses doing burnouts on the street. And a side of engine, trans or axle swaps.
Heck southern California alone probably has 5% of the people that take their vehicle offroad just bombing through the dessert pretending they are doing Baja.
I'd bet half of the true 4x4 vehicles in America aren't even road legal they have to be trailered to the offroading area. I know mine is illegal to drive around town in, it don't have stop or turn signals no fenders no vin no horn, the tires aren't balanced since they are 41" super swampers on 20" beadlocks.
Maybe 5% of people in a metropolitan area actually offroad their 4x4 the rest mall crawl, but in the rural areas we like to get muddy. In the country if you see 4x4 trucks in a parking lot they aren't mall crawling they are meeting up to go offroad somewhere.