I think Pokeballs are deflating because of how it's almost impossible to get 10,000 TBT now. Stuff like pinwheels don't prove this point, but there's less TBT in circulation now. Even artists hardly accept TBT for their work.
In all honesty, I am manually deflating certain items that will more than likely never (or at least rarely ever) be sold much with the hopes that their prices are "reset" and people pay what they want for them, because, let's be honest: who has 20k+ for a set of houses or a ball? Like.... a handful of people, maybe? The prices are really just ridiculous at this point (some have deflated a ton though, like choco cakes, tbt fair, etc.) but for the majority of actually decent ones, there's a handful of people here that are too stubborn to let the prices down at all, and until then, I can guarantee unless we get lots of restocks, prices won't change even with my extra "assistance."
TL;DR the tbt economy is screwed over unless the mods make tbt easier to get, we have more collectible restocks, or the rich people are willing to let a few pixel squares out of their possession