I think each head had its own good points.
I think Phil Harrison (first one in charge of WWS 2005-2008) has been the one who pushed the most innovative and creative projects, betting on ideas that in many cases were too ahead of their time. Stuff like motion based games and tech with Eyetoy or Move that were key later for the success of Wii or VR, user generated content games like Little Big Planet that were key to have later Minecraft or Dreams. Or PS Home, that was key to have later virtual words/metaverses.
Shuhei Yoshida (2008-2019) continued the legacy and refocused it targeting a more hardcore, traditional mainstream gamer who likes blockbusters instead of trying to appeal a more casual mainstream player via innovation and social games. Yoshida came here with a profile of an executive and producer of games, so understanding more the medium.
Hermen Hulst (2019-?) barely started, so it's difficult to analyze his work because continued the same previous strategy focusing on blockbusters and many key strategy decisions they took were in a good part taken recently were the extension of the previous WWS/SIE heads (to grow headcount of internal studios, PC ports and mobile games, betting harder on MP & GaaS, move regional XDEV 2nd party publishing to a dedicated studio that reports to XDEV instead of to local gamedev internal studios, to slowly add new markets for their game sub/cloud gaming, globalize all XDEV 2nd party stuff to a single worldwide team with presence in all main regions...).
Maybe the biggest change from the new leadership at SIE and WWS specifically with Hermen and Jimbo has been to bet harder on all these previously existing strategies and to acquire way more teams (Insomniac, Bungie, Bluepoint, Housemarque, Haven...), to grow all their internal teams enough to follow there the Insomniac path of making the big teams work in more games at the same time, also betting harder on collaboration between different teams (something they already did many times before like SSM+RAD, Guerrilla+Kojipro, ND+Bend) and a higher bet on the publishing of games from Japan and rest of Asia. Regarding the publishing of small externally developed games they now focus a more win/win situation for these studios and Sony: instead of Sony publishing them and keeping full exclusivity and the IP, they fund indies and help them selfpublish their games asking only for timed console exclusives and giving the indies their IP. Hermen came here with a profile of a gamedev and head of gamedev studio, so understanding more the medium and also the needs of the developers.
Every generation AAA games take longer and longer to be developed, so most of the Sony games published or announced under Hermen's era, or big stategical decisions announced now come from the previous SIE and WWS heads or are only an evolution of them. Probably, outside acquisitions, we still have to see the first big project started and greenlighted by Hermen. But in any case, the quality and sales keep increasing with every generation and WWS head.
Having way more teams and headcount, we'll have to wait a bit but the quality and specially quality of 1st and 2nd party games with Hermen very likely will be higher than before, will cover more gamer types and markets than before, and will be way more successful than before.
I don't know or care about these people, so whatever I guess...?
They are the ones who have been in charge of the Sony World Wide Studios (now known as PS Studios), meaning they are in charge of all the 1st and 2nd party games published by them and the internal 1st party studios who make them.