KDE's policy proposal explicitly allowed for contributors to not disclose that AI was used, which according to the FSFe and Software Freedom Conservancy, is not a good idea in legal terms.
“FOSS project leaders cannot make good decisions about LLM-gen-AI policy if they cannot survey which contributions were assisted, and how much they are assisted. Part of the contribution process should (at least) include a disclosure of what LLM-gen-AI system was used, its version (as these systems change over time), and a brief description of how the system assisted the contributor. This information should be included in a machine-readable format in commit logs."
Indeed, such disclosure can be an important foundational step to allow for the accurate assessment of the copyrightability of code that has been assisted or generated by AI tools, in order to assess their licensability into Free Software. Open and clear disclosure is a helpful step for the Free Software community to maintain a healthy licensing ecosystem, which is currently threatened by the legal uncertainties that come with the advent of generative AI.
Additionally, it is worthwhile for developers to document in some capacity the extent of human work that they have done in their software projects, whether it be the writing of code, the selection and arrangement of components within the project, or the extent of human modification of machine generated content.
Not to mention the ethical and environmental concerns with corporate AI usage, the use of which KDE was not interested in attempting to curb within its own project, which personally I think was disappointing, and even their KDE Eco group stated the policy was incompatible with the goals of KDE being a green project.