The fires were man-made back then too and there was uproar about it, and the situation improved a lot. But even then deforestation was still ongoing. So it's a step back, meanwhile the deforestation rate never reached 0.
Indeed, people are burning more this year than they did in the past few years – any burning at all has always been unacceptable, but if the current spike is what it takes to finally create some international outrage and put pressure on Bolsonaro, then I'll gladly take it.
The idea is that you can burn a small place, cultivate it for a few years and then abandon it so the natural grow of the forest regenerate it. And some years later repeat the cicle.
When the population is small it's fine because the time between burn and burn was enough for the soil and forest to recover. When the population increase the time gets too small and the forest has not enough tome to recover, and after a few cicles you have problems like reduction of fertility, erosion and desertification.