Coincidences happen all the time in media. Attack on Titan also has German elements. The opening song is obvious enough but as the movie may have pointed out (I can't recall properly), Erin "Jäger" means Hunter. They hunt Kaiju, Eren hunts Titans. Armin also means something basically like soldier - specifically "army man". German for army is Armee or Heer and man is mann so put two and two together and you can get Armin or Hermann, the latter being an actual name.
Probably not any worse than watching a video of yourself. Most actors will separate the character they're playing from themselves, so even on screen they can think of it as a different person - especially since they know all that went into it, the costuming, the green screen, maybe even some people they're playing off of not even having been there when they shot the scene.
But watching your own movies can probably be more disconcerting on a professional level: "Oh... they decided to go with that take" "I could've done better there" etc.
*shrug* I'm sure most actors like watching their movies and a lot of people who are not actors would like watching something they've starred in. But I can understand why some actors don't from my own experience with is
When I was younger, other people's opinions never mattered to me at all because I never heard any. I liked the prequels of Star Wars for their amazing choreography and CG and tend to block out the bad parts, making the movie more forgiving. I realized that ranting on something doesn't really make it go away. If you don't like something, the best you can do, is either be constructive about it, or don't talk about it at all.
Maybe it's just because I was a kid when I first watched it, but I always thought phantom menace wasn't all that bad. It's probably because the story revolves around a sci-fi kid who fucks shit up. Jar-jar still sucked though. I think that's why most people hated it really, all dat binks.