A song always loses some deep content when it is sung by another language, It happens for all songs. For me, Korean hurts my ears. Which doesn't change the fact that Korean musics and movies are popular in other countries.Cantonese was the language of the Canto-pop and HK movies which were the hit all over Asia, and the world. Jackie Chan, Bruce Lee and Jet Li hit movies were all in cantonese, if they really sound weird, the world would not accept it.
To this day, I think Mandarin version of some of the classic HK songs still cannot be compared to the original.
Like the Shanghai Bund song:
Mandarin really has so much sh, zh, and sounds really hoarse, like a horse hissing.
Mandarin speakers usually mock Cantonese as "bird language".