The factoid that gets thrown about is carbon emitted per energy released. Coal does better than wood on this super specific stat, but it's fossil CO2 we just dug out the ground, whereas wood from a managed forest used for other purposes is carbon negative if the alterantive is leaving it to rot to methane, because it's extracting CO2 from the air and then the managed forest is growing more trees that do the same, because we use wood for things.

There's complications and details, but overall if everyone is doing what they should its okay and most of the hype is fossil fuel propaganda. Windmills upset the worms etc.