It's a bit of a strange one with the Manics
They were probably the biggest British rock/alternative/indie band around the turn of the century - but, as you say, they consistently continued releasing new music since then - and the number of people buying it has dwindled (despite it being some of their finest stuff - both 'Journal for Plague Lovers' and 'Send Away the Tigers' are great albums)
There's a bit of a "Show us your setlist before we book you" about the situation. If they were to play
Motorcycle Emptiness
You Love Us
A Design for Life
From Despair to Where
Faster
Suicide is Painless
Kevin Carter
Everything Must Go
Your Love Alone is not Enough
Australia
If you Tolerate this...
You Stole the sun
The Masses against the Classes
The Everlasting
Motown Junk
Who would really argue that they shoudn't be in that Arctic Monkeys slot?