If we ever want 'true AI' then interacting with the world would certainly be a crucial component of building one. Text is a crucial component, but ultimately being able to 'see' gives one an entirely new perspective on what words mean. There's a reason after all, for why toddlers touch hot surfaces even after repeatedly being told that it will hurt - until they experience it for themselves, the word 'hot' doesn't quite connect even if they heard it dozens of times and have a very good abstract sense of what it means.