Nope. Crystal Logic (the song) repeats that riff and vocal melody so many fucking times before it finally gets to the bridge, for example. Divine Victim from this very round is pretty Necropolis-style. Open the Gates' title track is very repetitious too, and I also have Hour of the Dragon noted in my autistic list for its repetition (although I can't remember that one off the top of my head). Some of their thrash stuff (Whitechapel, Midnight Meat Train, etc) is similarly poorly arranged, even if it's not melodic enough to compare to nursery rhymes (which makes those particular songs even worse).
You'd have to give examples regarding other bands' commercial songs. Breaking the Law's vocal melody, for example, builds for much longer than most Manilla Road songs, and it's also a much shorter song. The verse is built on basically two (very simple of course) riffs, which repeat only twice each before going into the chorus. The main hook repeats a lot more, but that's because it's obviously one of the most instantly identifiable riffs of all time, and even there it's not just a cut-and-paste job, e.g. in the refrain after the solo there's a build-up prior to the repeat-chorus-and-end pop structure of the song. Breaking the Law has more interesting songwriting than any short ~3 minute Manilla Road song I can think of.