Why does lightgbm not fit my toy example but catboost does? (2 order interactions) [D]

Excerpt

I am trying understand how tree-based regression model handle the dependencies of the target variables on the interaction of explanatory variables. However my experiment revealed that my understanding about the fitting process of a lgbm is not correct. And I don’t know why. My experiment is quite simple: a target (for sake of simplicity only in [0, 1]) and two explanatory variables with two values such that the mean of the target is the same for each of the values of the explanatory variables. T