Having stuttered all my life, I agree that much of the damage is already done. I could be fluent tomorrow, and I would still hardly talk. Stuttering has beaten any real desire to talk about anything out of me. Sometimes I have stuff spinning around in my head that I feel I really want to talk about, but the idea of actually mentioning it to a friend doesn't even register. Normally I type out a long Reddit post, then realise it's not worth posting and delete it.