That's one of the things, but it's also adding a dedicated sidebar for AI. That's the sort of thing that should just be an extension, there's absolutely no reason at all why that needs to be something built into the browser.
Developers should be providing alt text themselves, but in cases where they aren't having a local image recognition model running to provide a description isn't terrible as long as it's either 100% local or completely opt-in.
The dedicated sidebar on the other hand feels very much like a cheap attempt to cash in on the AI fad.