Unfortunately, many folks who were left behind on the Titanic were not helped much by life vests as the temperature of the water killed them within a half hour. Your comparison between that and wearing masks was good though... just as sure as life vests largely didn't help those who found themselves in the ocean when the Titanic went down, masks are not saving everyone either as they have their limits.
Nothing is 100% effective in preventing Covid-19 infections. Masks (good ones) do provide at least 50% protection.
@Thirst2learn Scientific studies have shown they work.
[healthline.com]
[sciencebasedmedicine.org]
[ucsf.edu]
Whether you intended it or not your user name is very ironic.