I'd argue it was porn, anyone saying otherwise is being as naive as the filmaker. It was a bunch of nude muscle men, having their (often ashy) skin felt up by a problematic gay man, sometimes with hardon's dripping pre-cum, and gracious hole shots. If this was as bunch of women showing off their pussy, tits, and ass, there wouldn't even be a question that it's porn.
Many didn't even want their vids to be seen by the general public. One guy breaks down into tears, when he learns that he isn't getting paid till he gets naked.
So, we can call it whatever we want, and Vimeo can play cute with the content, but it was porn. You wont find those full videos on YouTube.