Right, but people were engaged in burning since the glaciers retreated. So there's no possible pre-burning ecology to return to since the glaciers are LONG gone

Right, but people were engaged in burning since the glaciers retreated. So there's no possible pre-burning ecology to return to since the glaciers are LONG gone and the mega-fauna all died. So we can have either unpredictable, large-scale burns or we can have predictable controlled burns that the ecosystem had adapted to for the better part of 15k years.