>>34671109Simply put, its combination of shit stats and small movepool is what made people turn against it. Everybody assumed once the starters were first revealed that Rowlets final evolution was going to be a fast sweeper dedicated to one type of attack while the others were going to be either tanks or supports.
Then the word got out about what all their stats ACTUALLY were, and as it turns out, Decidueye ended up getting the worst stat spread of the three, going completely against what people were hoping it'd be in the first place and instead being slow, frail and a "mixed" attacker. I put mixed in quotes because its special movepool is nonexistent which makes its 100 base special attack stat completely worthless. It doesn't have any bulk either and its only marginally faster than the other two starters by 10 points.
With its combination of shit stat distribution, a shallow movepool, terrible defensive typing, and a situational AT BEST hidden ability, its no wonder people turn on this thing.