Articles
Nicholas Theisen's The Problematic Gendering Of Shōnen Manga https://whatismanga.wordpress.com/2013/05/27/13a-the-problematic-gendering-of-shonen-manga/
mangabrog.wordpress.com Has translated interviews of & discussions between (mostly) shonen & seinen mangakas, like Kentaro Miura & Naoki Urasawa. https://mangabrog.wordpress.com/artist-list/

Other Writings
[i]Are Nekketsu Shonen Manga Sports Manga by Frederic Ducarme https://journals.openedition.org/comicalites/3194

Videos
YH Otaku YouTube video series Mangaka's Journey seems to focus (as of this moment) on mangaka's known for their shonen series. https://www.youtube.com/playlist?list=PLCV1YFKpmazr0sV94fsl7JTCTv-K1lhni

The Land of Obscusion has The TRUE & SECRET History of Shonen Action Manga!; the one linked is for the 2021 edi. but there's an earlier one that has since been unlisted. https://www.youtube.com/watch?v=YWj2C_x71CA
After watching that video I'd recommend viewing Yonkouproductions video The History of Weekly Shonen Jump as it gives a more nuanced picture surrounding editor's decisions in regards to certain stories. https://www.youtube.com/watch?v=QnAYJ56Uqvw