* Transforming a collection means doing boring for loops instead of one-liners.
* interfaces/duck typing is great. But hey, []interface{} does not fit into interface{}.
* Structs with fields are encouraged, but there is no uniform Uniform access principle and that sucks.
* etc
But definitely, my own "science" confirms that it turned to be out less of a problem (for my own usage) compared to better languages with more friction.