It's not a matter of the effort of learning, it's about whether the writing system is suitable or not. The Chinese family of languages has many homophones, so that could be the prime reason why they came up with ideographs. The original Korean language didn't. Now if they were to use only native words, Hangul is sufficient. But Korean and Japanese borrow words from Chinese on a large scale. They need to also borrow the writing if they want to solve the problem inherent in Chinese languages.

OTOH, playing Dragon Quest or Pokémon, which hardly have Kanji, is sometimes fun when you mistranslate the words with euphemisms.

Copying is not a problem by itself. The problem is, when you combine copying with nationalism. Due to nationalistic pride, people don't want to admit that they copied, instead they claim that they came up with it on their own.

Don't know who started all this. Maybe China, then Korea and Japan followed as a reaction due to China belittling Korea and Japan. But Japan wised up since then and stopped playing this nationalistic claim and blame game. I so hope that Korea and China will wise up too.