In the maze island event that just ended, I noticed that the Black H Chests gave about half as much food as they have in the past. That is ridiculous! It's already a disappointment to get food instead of Heroic dragons, but before this decrease at least it was enough food to be slightly meaningful.
In my specific case, I just reached level 100, so food in every other source increased. The black chests were giving enough to do one feeding step of a level 69 dragon, so four of them gave enough to level up a dragon on any level. Now it will take 8. Not cool.
I have spent 1500 gems on food every month in 2021. I will not spend another gem buying food until this change is reverted.
I have provided this as feedback to SP in every medium I know of. That means posting here too.