If we're bringing accenting into this (as with ghoti, that uses the "o" from "women"), then syllabaries are far from optimal as well, since Japanese has different ways of accenting each word that are not encoded into the syllabaries themselves. You then end up with having to memorize a vast array of combinations and how they work in different context. So it's not really a syllabary but an alphabet with more letters. Which is totally fine, but then calling it a syllabary creates confusion since people expect to be able to pronounce words easily, which they can't with only the word written (just like with "women" or "ghoti").
Kanjis are not a syllabary, they're originally ideograms but they're not really, some of them "make sense", some don't really. So they become mostly another layer of mapping symbols to meaning, except this time you have tens of thousands that can't be decomposed properly into smaller parts (like words with letters), which is terrible for many reasons.
On the other hand kanjis offer you the opportunity to play around with different meanings, in a way that you just can't in English. That makes Japanese richer and more interesting, at the cost of being a harder language. I'm glad both exist.
Kanjis are not a syllabary, they're originally ideograms but they're not really, some of them "make sense", some don't really. So they become mostly another layer of mapping symbols to meaning, except this time you have tens of thousands that can't be decomposed properly into smaller parts (like words with letters), which is terrible for many reasons.
On the other hand kanjis offer you the opportunity to play around with different meanings, in a way that you just can't in English. That makes Japanese richer and more interesting, at the cost of being a harder language. I'm glad both exist.