Maybe they mean the small types of dogs and cats that are usually called "-species name- Toy" ?
Also, truth be told, Being lower than a "Toy" while being a pet is really bad, no Pet is lower than a toy, since they tend to be more fun, empathic, etc. At least until we have some seriously advanced robo pet, anything that the toy companies produce will never remplace the fun and caring potential than a real pet have (even if the toys don't have stuff like needing to eat or shitting and pissing), in fact, the only true minor points a pet would have against a toy pet would be: would be basic biological needs and a non defined attitude. That's pretty much it.
Now with yukkuris....well....yukkuris tend to have way to many minus points, even as beings themselves they are low tier for many reasons, you can say that being capable of speaking while being a disrespectful, offensive and arrogant pet really makes them be in a lower stratus than a RoboDog or RoboCat, of course, this are average yukkuris we are talking about, if they were the Platinum type they may outclass any known pet, or at least the majority of them, since they could take care of themselves and if you have space, even feed themselves by making a garden with vegetables.