Carboniferous ended 350M years ago. Today lignin is biodegradable and thus does not capture carbon past tree living mass.
https://extension.psu.edu/how-forests-store-carbon
Or alternatively, wood can be used for increasingly complex construction, for example this wooden skyscraper:
https://www.thetimes.co.uk/article/berlins-woho-wooden-skysc...
Lastly, just increasing the carbon stored in living mass may be vastly beneficial.