There are leaders in the anarchist movement, make no mistake about that. What is different about anarchists is that we distrust leaders in general, and demand instant accountability. Leaders are fallable. Theoriticians make mistakes. People are blinded by their own privilege.
Anarchists recognize that and seek to check the power of individuals over others at every turn.
If a leader has good ideas that people agree with, then people will act on those ideas. But simply because someone had good ideas in the past does not mean that their ideas will be good in the future. Anarchists seek to empower everyone as full human beings taking part in every decision that affects them. There is no single anarchism. It has a broad back and can carry many.