Raldo is spot on, the complexity of gathering loot lists used to be greater than it is now, so technical limitations should not be an issue.

I'm not an RL tree expert, but a friend said that the tree nodes even looked close to the real thing - i.e. pine logs and branches coming from something that looks like an actual pine tree. Now you have those same nodes giving rather different things

Especially considering that oak logs are not in particular low supply, and that mahogany logs can only be found at Iron Lake, it just seems like a very strange decision both using in-game logic and out-of-game logic.