No, bounty hunters did not kill the ICO. Bounty hunters provide a valuable service to new projects. If anything hurts a new project it could be airdrops. Many people game airdrops and then dump them on the market.
Speaking of bounty, if you want to earn a bounty for testing a wifi sharing app (Aloha WiFi) join the Telegram community at- https://t.me/oppopenwifi and fill out the Beta tester form in the pinned message.