Forest fires are considered a contributor to global warming, but using firewood is considered carbon-neutral. I'm not sure I understand it. In both cases, only the carbon that had been captured several years or decades prior is released, why aren't both carbon-neutral (for that matter, even petroleum is carbon-neutral, applying a large enough timescale)?
Another thing to consider:
If burning wood for energy, it is generally displacing other alternative dirty fuels that would emit net carbon dioxide. However, forest fires do not displace anything. It's far better to harvest wood from forests and use it for useful purposes and replant a new forest than let a forest burn and replant a new forest.
However, for ecological diversity purposes, it may be useful to let forests burn. It creates environments that are needed by many species. If all forests fires are put out very soon, such environments are rare and the species dependent on them may go extinct.
Or, the best of both worlds: mostly harvest a forest, leave a few trees here and there, and then after harvesting burn whatever remains.
It's the timescale that's the issue.
Firewood is generally harvested from a managed forest; there's a continuous cycle of planting, harvesting, and burning going on, and the carbon dioxide released from this year's burning will be absorbed in next year's growing season.
Major forest fires are not continuous events. Even with a healthy fire cycle going on, the carbon dioxide released in a bad fire season will take a decade or more to be absorbed -- and for the past century, the fire cycle has been anything but healthy.