Correct. If you choose to install an app for the first time, you will get an "are you sure?" type of message that shows whether anyone in your web of trust follows the publisher of the app, but that doesn't show up at all for updating.
It would be nice if nostr:nprofile1qqs83nn04fezvsu89p8xg7axjwye2u67errat3dx2um725fs7qnrqlgzqtdq0 showed WoT on the app information page prior to tapping "install."