That Venus has a solid crust I think has been known for a long time, first evidenced by volcano features that appeared static. The interesting part here is that there is subduction that maintains a thinner crust, it's just occurring in place. Which makes me wonder, maybe this happens on Earth as well, and our more dynamic crustal movement is just an added feature.
Also, if subduction is a thing regardless of crust movement, that kills or at least puts into question one of the arguments of the Rare Earth hypothesis, that being crust movement is necessary for a functional carbon cycle, which in turn life depends on. Of course, Venus has virtually no water so that itself breaks any carbon cycle that could exist.