Alrighty so... I think you're full of shit.

What you say is true for passed down spoken language because errors like the ones we are talking about are transparent. Once you can write it down, the rules are evident and persistent. Nobody has to own them to say that as we transcribe language X these are the rules for conjugation, pluralization, etc. you can break them if you want, but as you say nobody owns the language: you need not be accommodated in your mistakes. Spoken language can change and the rules can follow, but being shit at writing (even if lots of people have the same problem) isn't something written language must accommodate.