Seriously, you have to stop comparing English to Japanese. It comes off as ignorant as when a Japanese person says the same things about English. You were born into an English family, so English seems logical. But that's it. Japanese is not unnecessarily complicated to Japanese kids.
Japanese has four verbs (that I know) for wearing. Hats cover, belts and ties fasten, shirts are worn, and you enter pants and shoes. That's the way it is and it's no worse than when a French person accepts all nouns as masculine or feminine.
Japanese has three words for be: です、ある，いる. That's how it is. Not complicated.
If a Japanese person complained that we use different words to put out a flame and turn off a light, when they are the same in Japanese, well, I'd be more polite than I am here, since they would probably be paying me, but I would explain that you have to accept that the languages are different. Just swallow it, accept it, and learn it. But being critical of it is nonsensical. It's a language, and whatever complication you find in Japanese, I can find more complicated, irregular stuff in English.
For example: what does 'ough' sound like? Four letters. Should be easy to say. Tough. Though. Thought. There you go. I've proven the absolutely unnecessary complication of the English language.