Problem is the appeal with this game and the desire of supporters is going to be skewed overwhelmingly towards growth.
Shrinking is a saturated area amongst "gts" games (its just that most of them are dogshit ones using unaware as the primary plot device, and the sterotypical "ah bugs *stomp stomp stomp*" trope). Giantess city has a wide array of games that can be found about on there that fit that desire.
But I'd say as mentioned, outside of a rare anomaly, shrinking isn't going to be something you'll see getting added in this game, if at all. Especially when content as of late has been somewhat reduced ( I aint changing that

), that shrinking content will get tacked onto the game when there's an entire arc yet that hasn't even begun is highly unlikely.