Concur here. He's said plenty, though the whole postmodern schtick obviously means their interpretation is frequently up for grabs. (Again, not a defence, but an observation.)
Let's also not sugarcoat that the festival has booked plenty of artists before with off-stage troubles too. Again, not a defence, but an observation.
If there is a contract at this point for them - I'm not sure, but if anyone could say whether there has been further movement on the sources who laid out this information originally - then it could be revoked if he is found to be in breach of it, of course.
He’s said worse - which isn’t a defence just an observation, I don’t think this particular outburst will torpedo any contract they had (if they had).
If it’s an issue of recency bias there’s a wider argument to be had on statute of limitations on judgements of character.
By all means replace them though!