Earlier quoted context omitted.
Not for beginners. But for fluent speakers, kanji are very necessary to distinguish all the homophones. E.g. 効果, 硬化, 降下.. are hard to learn, but they're clear. こうか is much easier to learn, but it could mean any of 10-15 unrelated things.
All of which native speakers have no trouble distinguishing between in conversation when there are no Kanji anywhere. It's the same with homophones in any language, usually the context makes it clear because the alternatives don't fit. The homophones in Japanese and Korean pretty much all come from the vocabulary they share with Chinese which makes up the bulk of the vocabulary for both those languages. One doesn't u…
I personally find the most difficult part of reading kana-only text to be detecting word boundaries. It's much easier when kanji is used, and I'm not even a native speaker.
An English analogy isthatyoucouldwritewithoutspacesandbeunderstood but it's more difficult to read and unnatural.
Young gen-z types on Japanese Twitter abbreviate everything, but even they don't drop kanji.