I am an Arctic Monkeys fan, just saw them in Oakland, but anybody who suggests they can headline is delusional. They have had one sort of hit in the US. That was IBYLGOTD. Which was released in 2005. The new album has not done anything to project them upward with American audiences since the last time they played Coachella. Which was 2012. When they were billed fourth.
I would be surprised to even see them on the lineup after such a short repeat, but they won't be higher than 3rd if they are.
And before we go there: Stone Roses/Blur were legends without American hits. Way different than a contemporary band without American hits. And 1901/Listzomania were absolutely gigantic songs. Clearly GV was counting on the new album producing similarly huge records, but like KOL, it just didn't work out that way.