Since Google only redesigned the Lens icon back during Google I/O 2019, the new variant comes as a bit of a surprise — after all, the 2019 icon already fits nicely into the icon color scheme that Google is slowly introducing for all of its apps
But it's entirely possible that many people might find the 2019 icon hard to understand as it only loosely resembles a camera, so a redesign that hits closer to the real thing might not be the worst idea