However, I do believe just multiplying trees by weight does not accurately describe what carbon sequestration is. Trees are not the only place carbon is sequestered in a forest. Soil sediment, animals, and other plants also sequester. It’s also a home of biodiversity and nutrient run off that assists other parts of our global ecosystem. In turn, Carbon sequestration occurs over time; and it’s these rich, biodiverse ecosystems that produce the fossil fuels that we are burning, without them the carbon would never sink into the earth as it does.
Eliminating the rainforest halts the engine that cleans the atmosphere and removes the carbon and cools the earth. It would also dump millions of more tones into the atmosphere (even by your calculations). It would also disrupt global food chains which do produce our global breathable oxygen.
I’m not sure what your point is that you are making other than you imply that we don’t need to save the tropics because fossil fuels are worse; but I heartedly disagree with that implication.