In my experience, it depends on the person and their involvement in the project wether or not they mind if their works are preserved. I have received all kinds of responses, from apathy, to excitement, to anger that their works are preserved. I've had people ask me to remove archived items, and I've also had people bend over backwards to send me versions and source code not yet online. It really depends on each situation.

However, I personally don't care if they want their works preserved or not. I don't ask permission if their work was originally intentionally made public, because by making it public, they have "lost" their right to control access. This varies from country to country and legal system to legal system.