I’m glad you brought this up because I actually think the comparison with toddlers makes my point.
A 1 or 2 year old can get just as much enjoyment from singing wheels on the bus or playing with a new toy as they can from a trip to the zoo. Often, the outing is more for the adults than it is for the child.
So if this person genuinely had the cognitive capacity of a toddler, would it really make much difference to him whether he was at a crocodile zoo or in a sensory room? If anything, the sensory room would probably be more beneficial and certainly safer.
To take the comparison further, people often criticise parents who bring toddlers into places where their behaviour negatively affects others, even though crying, shouting and running around are completely normal toddler behaviours. We expect parents to consider the impact on other people.
So why is it unreasonable to ask whether taking someone with the mental age of a toddler, but the strength of an adult man, into a place full of vulnerable children was the right decision? I'm not saying people with cognitive disabilities should be locked away. I'm questioning whether the benefit of this particular outing outweighed the risk, and whether there were safer alternatives that would have provided the same enjoyment.
Who actually benefited from this trip, and was there really no safer activity available?