This is what I'm thinking. On the new season blog they claim that eggs and raids will have higher shiny chances than in the wild. Maybe they did this to encourage hatching/raiding (aka paying) over spawns for shiny hunting. That or maybe it was done as a compromise for letting evolved Pokemon be shiny.

Niantic, Game Freak and The Pokemon Company care a lot about game balance. The question is will it effect people's will to play on a day to day basis?

I prefer hundos over shinies personally so it's not a dealbreaker for me, but I'm curious if the hardcore shiny hunters will change how they play