I've seen both commentaries for Worlds in English and Korean.
Now I only watch in Korean because
1. Korean commentators (some) actually know what they are talking about because they used to be pro players.
2. They invite current pro players as guests to hear their opinion, and get advanced, high tier tips.
2. English commentators are so... bad... they spew garbage out of their mouth like silver players.
AND TO MAKE THIS ALL WORSE
When I give tips on things, players say NO THIS, NO THAT, and yet I'm legitimately sharing the opinion of pro players or their streams.
NA players are so spoiled because they are so oblivious to understand what they are doing. A part of it must be this crappy knowledge that's being shared by all the ignorant players, including the NA channels.