I...really don't see an issue here.
Believe it or not, Irons bad mouthing a film he was in doesn't mean that much in itself, and can suggest a number of options:
1) He hadn't seen the film before promoting it, and was in no position to give any comment on overall quality bar what the studio would expect (actors to stand by their work)
2) He genuinely thought it was a good film, but had a change of heart (which isn't unheard of - opinions change after all)
3) He was lying of his own volition.
In likelihood, it's a combination of 1 and 2. If you put your heart into something, it's not always apparent concerning lack of quality (I can attest to this personally), not to mention that quality is subjective. And even if Irons had known from the start, what could he say? "Yes, the film I'm in is bad, now please watch as the Warner Brothers hammer comes down."
Believe it or not, Irons bad mouthing a film he was in doesn't mean that much in itself, and can suggest a number of options:
1) He hadn't seen the film before promoting it, and was in no position to give any comment on overall quality bar what the studio would expect (actors to stand by their work)
2) He genuinely thought it was a good film, but had a change of heart (which isn't unheard of - opinions change after all)
3) He was lying of his own volition.
In likelihood, it's a combination of 1 and 2. If you put your heart into something, it's not always apparent concerning lack of quality (I can attest to this personally), not to mention that quality is subjective. And even if Irons had known from the start, what could he say? "Yes, the film I'm in is bad, now please watch as the Warner Brothers hammer comes down."