You are cherry picking quotes. This is from the abstract:
"Our results indicate that nearly all the observed increase in BA is due to anthropogenic climate change as historical model simulations accounting for anthropogenic forcing yield 172% (range 84 to 310%) more area burned than simulations with natural forcing only. We detect the signal of combined historical forcing on the observed BA emerging in 2001 with no detectable influence of the natural forcing alone. In addition, even when considering fuel limitations from fire-fuel feedbacks, a 3 to 52% increase in BA relative to the last decades is expected in the next decades (2031 to 2050), highlighting the need for proactive adaptations." - "BA" is "burned area"
This is from the conclusion:
"These findings strongly indicate that the observed increase in BA was primarily due to increased fuel aridity and not due to simultaneous variations in nonclimate factors such as human effects on ignitions, fire suppression, or by altering land cover (similarly to the conclusions by refs. 1 and 42). Our results suggest that changes in human environmental factors, including changes in biomass and fire management practices during the period of record, did not significantly affect the stability of the climate-fire relationship at the scales analyzed here."
I'm not saying fire suppression policies had no impact. I'm saying that they are not the only cause of the fires. Furthermore, I am saying they aren't even the primary cause, and it's not close.
"Our results indicate that nearly all the observed increase in BA is due to anthropogenic climate change as historical model simulations accounting for anthropogenic forcing yield 172% (range 84 to 310%) more area burned than simulations with natural forcing only. We detect the signal of combined historical forcing on the observed BA emerging in 2001 with no detectable influence of the natural forcing alone. In addition, even when considering fuel limitations from fire-fuel feedbacks, a 3 to 52% increase in BA relative to the last decades is expected in the next decades (2031 to 2050), highlighting the need for proactive adaptations." - "BA" is "burned area"
This is from the conclusion:
"These findings strongly indicate that the observed increase in BA was primarily due to increased fuel aridity and not due to simultaneous variations in nonclimate factors such as human effects on ignitions, fire suppression, or by altering land cover (similarly to the conclusions by refs. 1 and 42). Our results suggest that changes in human environmental factors, including changes in biomass and fire management practices during the period of record, did not significantly affect the stability of the climate-fire relationship at the scales analyzed here."
I'm not saying fire suppression policies had no impact. I'm saying that they are not the only cause of the fires. Furthermore, I am saying they aren't even the primary cause, and it's not close.