At least with the sleeping animations, the scenario is something you will see in several scenariosYou say that, yet there's actual sleeping animation for every pokemon due to pic nic and they don't play in battle when they're asleep...
(They did fix the eyes not closing bit, at least)
Wild pokemon will fall alseep occasionally, even in Area Zero (sleepy great tusk........very cute)
I think if you have them out in Let's Go long enough one of their animations is to just fall asleep
And finally if you picnic at all Pokemon be like "anyone going to sleep?" and not wait for an answer. And if you breed at all now you see it all the time forever.
Even when Pokemonamie had a million exclusive animations, that also made sense because its designed for you to see them. IT's a dedicated interaction.
Here? You have to specifically be standing idle in in a timed scenario wehere you're meant to be constantly on the move.
Either an oversight or they're meant to do it in specific environments and the Star Battles just happen to trigger them as well.By the looks of it, each mon has 3 animations during the Team Star Training sessions: one is a generic attack animation, while the other two seem to happen during these sessions only (which, as you rightfully said, makes little sense; why would they model custom animations for every single mon and only use them in a single scenario?).
For example, Gallade's are: skyward battlecry (special attack animation #1), side glance to both sides (TST exclusive), right shoulder stretch (also TST exclusive)
Meanwhile every other animation that plays during Let's Go / Picnics are: skyward battlecry (again), small bow (interact), kneel and sleep, angry negation (from pokeamie, triggered when commanded to autobattle a shiny or when in the water), shake (when you are washing him). I have not seen any of the TST animations in these situations
I wonder if they are meant to play in some other unknown situation and / or the fact that they don't is an oversight (very possible considering the current state of SV )
Sprigatito line's idles in particular seem like they'd be used in towns, since it's performing tricks.