Walking on that would be no big deal. I’ve climbed fixed structures far higher than this.
I would never dream of riding a mountain bike on it. I am way too un-coordinated plus I’d worry how they were going to get my broken body out of there.
Offroad motorcycles with 38.9 inch seat heights are even more scary. Try to put your foot down — nothing. I stick to the jeep roads and easy trails by and large.