Anonymous, open contributions can help to quickly collect data from a wider community. People can be quickly converted into contributors.
By allowing anyone to edit anything, you and the community will be able to quickly react to poor quality data, spam or malicious edits, through Retrospective Review.
While this can be a useful approach, particularly in small groups or team of contributors, in practice it has many downsides. By not having Attributable Contributions you are unable to recognise the work that people do, apply Escalating Blocking or build Moderation and other workflows that require some knowledge of the contributor.
It is important to evaluate whether anonymous contributions are the right approach. Balancing the needs of contributors (e.g. privacy) versus the needs of data users (e.g. trust in the contributed data) and the project.