If you place an oak sapling next to any other blocks, including logs, pistons, etc, it will still grow, either naturally or when you use bone meal on it.

However, other one-wide tree types do not grow if there are blocks beside the saplings. This is a very odd inconsistency between oak and the other sapling types.

This seems to vary between block types; for example, we were able to confirm that all tree types will still grow with dirt next to them, even though they will not with logs next to them.

Compare vs Java where all tree types can grow with blocks placed directly beside them.

Video demonstrating attempts at growing all four sapling types beside three different block types, using bone meal: https://youtu.be/HGCFOA4pgzc