Seeing a mid-career researcher having > 30 papers half way through 2020 (> 1 pp/wk). I'm still puzzled on why someone wishes to publish that many, & how much did they spend on each manuscript which often has n++ number of revisions, let alone other duties (supervision, admin)

It's likely that they had some papers submitted and accepted in 2019, and have a very large network of productive collaboration. # of publication of each hyperprolific scientists is overwhelming: https://www.sciencemag.org/news/2018/09/some-scientists-publish-more-70-papers-year-here-s-how-and-why-they-do-it

Not sure if this is healthy and sustainable for science. In particular, when it is viewed by early career researchers. I still recall how overwhelmed I was when doing literature during my PhD study and reading about "publish or perish" in academia.