In 1941 it would probably not have changed a lot. Even if in 1940, at the height of the battle of the Atlantic every German U-boat had anti-sonar tiles fitted, they would still be just as vulnerable on the surface and still suffer from convoy escorts carpeting the whole area with dept-charges as soon as some lookout sees a periscope. It would take until the introduction of the 'modern' type XXI and XXIII u-boats in 1945 to actual have a use for anti-sonar devices. And even then it would just spark an arms race with the Allies to develop better sonar.
What really doomed the German u-boot campaign were 1) The limited underwater speed and range of the type VII and type IX 'diveboats'. Spending the majority of its voyage on the surface, the u-boots were still prone to detection by long-range patrol aircraft, aircraft from convoy escort carriers and convoy warships.
2) The interception of the U-boot communications. Not only the breaking of the Enigma code but also what we today call the metadata: Who is calling when and from where. Once the British had set up their chain of listening posts they were able to at least rudimentary triangulate the position of every call and give advance warning to the convoys nearby.