Paper: https://www.nejm.org/doi/10.1056/NEJMoa2309822
My flatmate showed me this paper and I switched my reusable plastic bottle to a glass one. Funnily, his father's friend, who runs a plastic production company and has a PhD in chemistry, said that he always avoids drinking water out of a plastic bottle.
Mhh yeah; however, the study itself makes no statement about plastic bottles. On the All-In podcast, they also said that they'd switch over to glass bottles, but the issue is that the microplastic concentration in the body may also be related to other behavior, e.g., eating microplastic-contaminated foods or whatever. I couldn't find anything conclusive.