One reason I've heard is the much higher cost (and lower availability) of appropriate lumber. The forests were mostly cut down hundreds of years ago, while in north America, that process is still underway (though thankfully slowing a bit).
And yes, we have tree plantations, but they're mostly sitka spruce, and there aren't _that_ many of them compared to potential demand for wood.
No it's not, the total amount of forest in the USA is increasing.
It is still way, way down from the levels when Europeans first arrived.