If I'm correct, the different nikkud signs reflect the phonology of Biblical Hebrew where vowel length was phonemic (and maybe there were also a few more vowels?), but since this is no longer the case in Modern Hebrew, why wasn't a simpler nikkud system created? For example, why do we still have to have 4 symbols for [a]?
Ok, I guess one could say a similar thing for some letters of the alphabet, e.g: why do we still have ayn? But the nikkud is supposed to help you with learning how to vocalize words, so why make it unnecessarily complicated? And do native speakers even know which is the right nikkud for any word? (yeah, I know it's usually not used but I was wondering, if a native speaker wanted to, would they be able to write words with the right nikkud?)
Or maybe I've been wrong all this time and all the different sings do actually have some usefulness in Modern Hebrew too?