On topic, I am shy as well and dislike sharing stuff publicly. I only did it a couple times. I will never really do NSFW roleplay in public either because I don't want people to read everything that I do especially when I feel that I do not do it perfectly. It will just be awkward and embarrassing for me. In the case of my social life, I had a really bad history of aggressiveness with people so I will often feel shy or rather be afraid of showing that side of me to people I want to have fun with.
I could perhaps win over it in SFW roleplay as it does not require as precise attention on details and emotions. I can easily give personality to my characters but I won't always do it in public. I'm too secretive and embarrassed to show my writing to everyone else. My characters also hold a certain importance to me so I don't really like sharing them to the world. I use specific characters made for public if I must.