Why is it so hard to find a writing workshop for adult fiction writers?

I'm an older adult fiction writer who has been working on a novel for a long time. It's time for others to see it and I'm ready for feedback. It is a fantasy horror novel. I did find a writing workshop for fantasy and science fiction writers and my first review went pretty well. I couldn't find anything like that for horror. It seems the horror community is geared more towards movies and video games than writers. Why is that? I can't even find a Facebook group for adult writers. I've found a Facebook group for young adult writers. I found a couple of websites that were designed for poetry. I've found a Facebook group for horror writers but it's a mix of everything and it doesn't seem to have a lot of traffic. I've had trouble getting feedback from the Fantasy and Science Fiction workshop I'm in. I want to join a workshop for horror writers so that I can get feedback from people who are familiar with the genre. And that is not happening. I even joined a group for indie horror writers and I got a couple of people who were interested in reviewing my work but they never followed through with it. I even found a group for Horror Writers of America but it was a mix of everything. It seemed to be more geared towards professional writers. It seems to be a lot of writers. I guess what I'm looking for is a workshop for horror and a workshop for fantasy. I'm finding a lot of places that are a mix of everything but I want to join a workshop that is specifically geared to either fantasy or horror. Both of those genres have their own specific story telling method ways. Does anyone know of any writing workshops that are specifically geared towards horror or fantasy? Am I just out of luck?