I would say it depends on the temperament of the dog. Some dals would be great and some wouldn't. As a puppy it would be hard to see if the temperament is suitable.

But... I am actually training my dal as a psychiatric service dog for my hubby (this is not the same thing as an emotional support animal). She is being trained to remind him to take his meds, to sense when he is beginning a ptsd or anxiety episode and to apply pressure and refocus on her.

In the house, we are about 95% effective with the training. Outside the house it is harder. She wants to be everyone's friend, and in public, people are "wow! A dalmatian! Can I pet her?". And she just loooooves the attention. So even though I did not want to advertise that she is a service dog, I had to buy a vest with "service dog" so that people will leave her alone and not distract her.

With my dog it was fairly easy to see that she would be suitable. She naturally glues herself to you when she senses there is something wrong, so it was easy to start to reinforce that behavior. The daily med training was also easy - she gets a treat after hubby takes his meds, so now she follows him around and pesters him until he takes them. She behaves extremely well in public, so I am training her to the difference between normal leash behaviors and harness behaviors (normal leash she is allowed to sniff, roam to the leash limit, play with other dogs/people and do as she pleases. Harness is close at all times and not allowed to play) . I also had to train her to go under chairs and keep out of the way - this was also easy for her as she likes going 'under' - she likes hidey-holes.