It's a very expensive outing for very little reward at that age. What things do you think they'd enjoy? It'd be cheaper to do those things elsewhere independently.
We went when I was PP at 6w 😂 I go w friends and family. So it’s not just the baby/child I’m going for, I usually get invited or invite my sister/friend. At that age he’ll like the toddler rides, farm animals, maybe motorbike show, and the stage performances. I take them any age anywhere but at 16m yes there’s plenty there for him to enjoy. We go every year.
It might be stimulating (in a good way) just because it's a new environment and new scenery. I'll be taking my 2yo and 10mo. I've never been, but I'm sure there'll be things they can enjoy, like the petting zoo and hopefully there's rides for toddlers. My 2yo loves the kiddie rides, I just put the baby in a carrier and he seems to like it too, so I'm sure there'll be things that a 20mo would love