Wood floors are best with natural fiber rugs placed in the area between the speakers and the listeners is best.
Synthetic carpets are not great, and covering the floor with a single monolithic carpet is not good.
Why? A wood floor consistently reflects sound equally pretty much across the spectrum. A natural fiber rug will have a broader, smoother absorption characteristic, and multiple rugs of different thicknesses and materials will create a more complex absorption character which results in a more balanced, natural sound in the room.
A synthetic material generally has narrow, spiky absorption characteristic. This is not terrible for a portion of the reflective area, but covering the entire floor with a poorly behaving synthetic materials amplifies the problems with those materials.
Also, a wood floor with multiple rugs can be adjusted and altered as the room acoustics are added or altered.