Well, I don't know if it's an unpopular opinion, but I think the most annoying enemy in the franchise are Skyward Sword lizalfos:
They're so freaking immature and annoying, they stick out their tongue at Link to mock, provoke and taunt him with their tongue out and they make those "warg, wargl, wargl" annoying sounds (someone even joke about the "wargling" in the comment section of the video). How are you supposed to take that clown enemy seriously? I freaking swear, back when I was playing this game I wanted to use the shield bash to make those immature and annoying lizalfoes see thirty-six candles and tell them to grow up (but I've always struggled with doing the shield bash or timing it right, my timing was off and I just had a hard time with it, I should have practiced a bit against the log in the Training House in Skyloft but I never even thought of that, I guess it doesn't really matter any more since I haven't played Zelda games for years and am not likely to play them any time soon) and then hack the bejesus out of them. I heard that people had fun using the shield bash to knock enemies off balance, that's something I would have enjoyed doing back in the days.
Some people (including a person who posted a comment in the comment section of the video) complained that the controls are horrible in this game. Well here's my take on this. Sometimes they are (horrible), sometimes they aren't. I had to rage quit after like 80 attempts at playing the harp with Kina just right at the Lumpy Pumkin to impress a crowd enough to get a piece of heart (at that point I just decided that the stupid piece of heart wasn't worth getting so angry and worked up over it). At no other point in the game did I have a hard time playing the harp, but for some reason I couldn't satisfy that crowd and get the piece of heart. And the controls were also horrible in segments of Twilight Princess, I always turned the motion controls of during the flying segments, it makes those segments so much easier and I didn't have to rage at the overly sensitive control or sensor bar.