Pretty insensitive remark. The families, ex-shipmates, and many others still alive from the WWII era, remember the guys and officers from the Indianapolis.
You speak from youth, and from the leavings of the culture.
Almost everyone on the planet soon knew the story via that scene.
But historians and military buffs had and would have known the story without seeing ‘Jaws’.
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Including my late Dad—who flew a PBY Black Cat on open-ocean rescues—families and shipmates seldom spoke of the war. My Dad only mentioned a reunion, where some he had rescued tearfully hugged him. It's certainly possible he might not have known the ships' names!
Any survivors "sensitive to my remarks" would be in their 90s today.
As a student of WWII—and although I knew of the USS Indianapolis tragedy—I was reminded of the story from "Jaws", as it was recounted at a boating forum—in 2012.
I actually never saw the movie...! .