If its and it's are used "incorrectly" long enough, it's possible the conjunction will lose the ' through use. Descriptive vs prescriptive etc.

Also, in response to the person you are responding too, there are advantages for our writing system not being entirely phonetic, namely that different dialects of English that may not be easily interintelligible via spoken word are interintelligible via writing. Like a weaker form of the same benefit of the Chinese writing system.