Nothing will happen.
As usual segments of ARMY will rant, abuse etc , but that they will do even if BTS tops SKZ, that's just ARMY being ARMY.
BTS is already a veteran group, their legacy and fandom is secure and they will sell out to those fandom.
Just that there will not be massive influx of new fans, they had in 2018-21 period
So yes, it is possible that SKZ will have a larger tour.