Learning the size of objects using pure text analysis requires significant gymnastics.
Vision demonstrates physical size more easily.
Multimodal learning is important. Full stop.
Purely textual learning is not sample efficient for world modeling and the optimization can get stuck in local optima that are easily escaped through multimodal evidence.
("How large are lions? inducing distributions over quantitative attributes", Elazar et al 2019)
Ask a blind person that question - they can answer it.
Too many people think you need to "see" as in human sight to understand things like this. You obviously don't. The massive training data these models ingest is more than sufficient to answer this question - and not just by looking up "dimensions of a lion" in the high-dimensional space.
The patterns in that space are what generates the concept of what a lion is. You don't need to physically see a lion to know those things.
Twice of half of its size.
You are not wrong though, just very incomplete.
Your response is a food for thought, IMO.