The simplification was necessary because as more of the population became literate, the general public had to have the ability to create words as well. Languages like Japanese took a half and half approach. The characters could still represent something, but they were so simplified their meaning could be extended over a large range. English on the other hand became totally textual which is why this whole debate can even exist. Using words to describe an object was much simpler than creating separate images for each and every thing in the language.
Pure text is very powerful.
I can give way to abstract ideas very simply, while images cannot do this as simply. Verbs are extremely difficult to express in image. We know what it means by direct visualization. The word is then broken down phonetically and the end result represents run, in meaning and pronunciation. To do the same in image is hard.