Well, a little update on my experiment into AllTrails. As I'd mentioned, I "logged in" via my Google account, as offered, without creating any type of account on the AllTrails site. I had been immediately able to post a trip report, but not able to post photos. In my trip report, I made it very clear that I'd done the hike nude.
My Carrizo Gorge Railway trip report, as "Jim T":
https://www.alltrails.com/trail/us/california/carrizo-gorge-railway?search=trueWhen I accessed the site yesterday, I found the "Upload Photos" button. It may have been a new account delay, or I may have simply overlooked it the first time. If you click "Photos" at the top banner, you'll see the photos for that trail, but no upload button. If you click "Photos" down near the "Write Review" section, you'll get the upload button.
At any rate, I was able to upload four photos from my hike. One shows no nudity...well, my shadow was nude, but that's all you see of me. Another showed me, with some brush obscuring my bare backside...if you look closely, you can tell that I'm nude, but it's not real obvious. Another shows me walking toward the camera across a trellis...fully nude, but somewhat obscured due to sunlight from behind. In the thumbnail, it's not clearly obvious that I'm nude, but if you enlarge the photo, it's obvious. Another shows me walking through one of the tunnels, fully nude and in view, but in the dim light of the tunnel interior. Even in the thumbnail, it's easy to see that I'm nude. If you enlarge that one, my backside is plainly visible.
So, I suppose time will tell as to whether nude photos are supported on the site, or if they'll be deleted. If the photos stay, I'll try adding a few more on some other trails. One thing is that these are on an established trail page, not a new trail submission. My photos are among over 900 other photos, although they are currently displayed near the top of the list. If nude photos were uploaded while submitting a brand-new trail for the site, they might not be accepted.
Maybe if a few of us "free range" a few photos onto the site, it will become accepted. The site's rules don't specifically mention "nudity", but they do say they don't want "selfies". So maybe trail-focused photos, that just happen to have a nude hiker somewhere in the shot may be tolerated. If you give it a try, be sure to let us all know how it goes!