(Affects full versions 1.16 and up but I don't see an option for that). All other trees can grow without horizontal clearance at sapling level, including dark oak trees. In older versions 2x2 spruce and jungle trees could grow in the same way. However, now any block in a 3x3 area around the northeastern sapling won't let the tree grow. This includes other saplings even of the same type (not including the 3 other adjacent saplings that are part of the tree), dirt, grass, podzol, mycelium, logs, leaves, and dispensers that are trying to grow the trees. As interaction with the sapling in any way requires interaction from the sides or top which would prevent growth, it is really bad that these trees won't grow normally.