have you actually read anything? indigenous were pointed as responsibles for cultivating dominant species which had an impact and shaped the flora. the last website i published is a whole book showing how its rich biodiversity happened over multi million year processes. it also points out the impact on the "funneling" of species indigenous occupations had

i still think despite their impact, they were exemplar compared to what we had on the rest of the world (but i never studied Asia). but it's not like they were magicians that had no impact on anything and lived in complete synergy with nature by increasing biodiversity. and if you think cultivating biological dominant species across a forest has no impact i suggest you to research on the many examples of alien flora effects on various ecosystem on modernity or even try to throw some Hawaiian Baby Woodrose somewhere out their native land to check how much these species take over anothers. they probably killed and reduced species expression to settle themselves there. but cest la vie. living has an impact after all