A group of former top Sony Corp executives has delivered an unusually blunt critique to the firm's chief executive Kazuo Hirai, accusing him of losing sight of innovation by focusing on cost-cutting. At a meeting at Sony's Tokyo headquarters last Thursday, five former executives, including PlayStation creator Ken Kutaragi, took Hirai to task for failing to encourage the kind of creativity that helped produce iconic gadgets such as the Walkman, according to three people familiar with the meeting.