You're making a common mistake here, in conflating pigs being compatible with toddlers based on a very limited scope test, with being comparable to toddlers in general, which they are not remotely close to being.
Pigs are comparable to dogs, but dogs are much more impressive overall. Lookup dogs like Chaser, for example, and show me a pig that has ever come close.
People think that dogs are special because they have relationships with them. But that doesn't really make dogs special except as far as the relationship is concerned.
The point is when intelligence of animals is evaluated like this, it's evaluated in very limited scopes, e.g. arithmetic abilities, mental time travel capabilities, abstract thinking capabilities, etc.
To generalize the results from one limited scope test to intelligence in general is flawed and wrong.
> The experimental evidence seems to indicate that pigs are probably smarter than dogs.
It indicates nothing of the sort.
[1] https://www.technologyreview.com/2024/05/07/1092127/the-way-...
I would based on my experience say the pigs are more intelligent than dogs, even the sheep dogs which are some of the cleverest I have seen.
The pigs would be solving problems, building things (the first thing in a new place was always a latrine), organizing their environment but then would take well earned rests. There was a social dynamic to them that was also kind of interesting.
It can be hard to compare the two since we can't compare their intelligence overall as one thing, but have to compare specific subsets, showing dogs and pigs are intelligent in different ways.
I think any claim that one is outright more intelligent than the other is dubious.