Those are the actors who played Duncan Idaho in the David Lynch adaptation and in the two Syfy miniseries. So, yeah, it's not wrong, just incomplete — though I have no idea why it only serves up those three. There's certainly no limitation to three images, as can be verified by searching for "Sherlock Holmes actor" or the like.
Clearly everyone working on google knowledge graph are a bunch of dune movie purists who don't recognize the existence of the 2021 film for being too hollywood.