Michael Caine, in that 1970’s time-frame, was heavily influenced by his (drop-dead-gorgeous) wife.
Middle-east politics and religious concerns are foremost in his work of that time.
Reference: “The Man Who Would Be King”.
He was probably just influenced by paychecks. British actors are notoriously mercenary, they do the work to the best of their ability and move on. Caine’s admitted to not even seeing many of the movies he’s been in, he just doesn’t care.