I don't have anything against a gonzo "let's go and ventilate Hitler and a few dozen of his murderous buddies with a bunch of cool modern weapons" story, but I do really want at least a bit of historical research done.Do not recall this, but yeah, that's just silly. There is nothing wrong with going back in time to kill Hitler, but you have to do a bit more to make it stand out and do something with it. As in, if your book is all about killing Hitler, then it's a bit silly. But if you bump him off in the first chapter and then lots of things happen different and some things stay the same, then okay, I'm there.
And it's super easy to make it more interesting, like I said--just make it "Mossad team and Palestinian infiltrators/special forces that probably don't exist IRL get stuck in the past together, must work through mutual loathing to kill Hitler and save millions".