In answer to the title question, yes, unquestionably yes. White people do dominate the outdoors.
We are outdoors people and we travel. There are three outdoors groups: 1 The KOA big RV rich bunch that travel trough the outdoors. 2 The National Park/State Park set that has the save the earth types and smaller RV’s that get out and hike, bike and camp. 3. The back woods types that really rough it, ATV’s, truck campers, tents, guns and they hunt.
We are type 3 and also live in the woods.
Never, ever in our lives have we seen a Black family in either type. Hispanics and Asians, occasionally. Never a Black family.
Going to triathlons you see about 1% blacks. Just look at fun runs and see how many minorities there are....probably 20% at the most.
But...they do like the clothing....so model away!
You forgot a 4th type; also white—my type—glamping and day hikes!