In 2000s, Taiwanese music industry used to copy Korean songs without permission or remake the songs with the approval. The social media was not big then, Koreans did not know about Taiwanese music market as much as Taiwanese people did not know about Korean music market.
Will Pan plagiarized Korean songs without any permission other than 我讓你走了 that he bought the copyright from the Korean singer and 快樂崇拜 that he got the approval.
He's been accused of copying 20 Korean songs without any permissions from 2000 to 2007.
He also did in 2017, but he made an apology because K-POP was pretty big in Taiwan at that time.
His biggest hit song is 不得不愛 which copied Freestyle's Tell me Why without any permission.
Freestyle filed a lawsuit in Taiwan against Taiwanese singer Wilber Pan for illegally plagiarizing their song "Y (Please Tell Me Why)". However, the Taiwanese court dismissed the lawsuit in the first instance because Taiwan did not officially recognize the copyright of South Korea due to lack of diplomatic relations at that time.
Do people know about the stories of his songs ?
He still seems so popular.