That anon is just embarrassed lmfao. Indicating the t+b in the tags are really helpful for creators who only prefer a certain dynamic. Helps make sure that people who may want to follow them think twice about it and avoids having even more followers that bother them with comments like 'lol how can you make x a top,' 'can you draw y as a bottom,' 'not my thing lol personally i prefer z but pretty art!!'
I die inside every time I see someone say 'haha i don't like this dynamic but your art is pretty'