ECDIS does much more than just simple google style nav. ECDIS also understands ship draft, water depth, turning radius, etc and is designed to keep the ship from doing something stupid like the Valdez did. ECDIS also looks for dynamic collision dangers fro other ships with radar feeds. So even if a ship has paper charts, the regulators, insurers or owners will not risk a drowsy watch running into a rock thus risking life, limb or billion dollar damage/fine payout. Would you fly intercontinental if you knew the plane only had paper charts and a sextant?