Earlier quoted context omitted.
Checked and it was published through Nature: Jiang-Xie, LF., Drieu, A., Bhasiin, K. et al. Neuronal dynamics direct cerebrospinal fluid perfusion and brain clearance. Nature 627, 157–164 (2024). https://doi.org/10.1038/s41586-024-07108-6 Every Uni should have access through your library system.
Yes, it was published through Nature. But what stops Univ' site to have original research paper available for download? Nature magazine is just a distribution channel (they did not sponsor the research so should not have exclusive rights on it). Left college long time ago; and do not have access to any library system.
If you want to publish in an Open Access manner, you need to pay the costs. Or if your country wants to license it for Open Access, your country pays the costs.