To be clear, the 'require' part of this petition is not targeted at researchers, but at publishers.
Publishers want to own their papers' copyrights, and have exclusive publishing rights. The fairness of this is questionable when they aren't paying for the core work done to produce the papers. They apply a lot of pressure to keep research behind paywalls, often against the will of the funders and the researchers. The idea of this petition is to give researchers and government funding agencies some legal strength if they want their work to be freely available.
Publishers want to own their papers' copyrights, and have exclusive publishing rights. The fairness of this is questionable when they aren't paying for the core work done to produce the papers. They apply a lot of pressure to keep research behind paywalls, often against the will of the funders and the researchers. The idea of this petition is to give researchers and government funding agencies some legal strength if they want their work to be freely available.