The spruce trees that are grown by saplings only grow the regular 2x2 variant not the old growth pine
steps to reproduce
Get bonemeal
Get spruce sapling place in a 2x2
Grow the spruce sapling
observed results
the spruce tree will always grow the regular variant.
expected results
spruce sapling should also grow into 2x2 sapling old growth pine variant
The image shown shows the large pine taiga variant which isn't possible to grow with saplings because it will only grow the regular large spruce variant
This is not a bug, tall birch trees also cannot be grown from a sapling. I think this is to try to make players have to go to those biomes to find the other tree variants.