Illiteracy is practically non-existent in japan, and I'd honestly be impressed if you are able to write kanji, but then consistently make the same mistake of misusing a particle. This is akin to being unable to use tenses in english. Imagine not understanding how to use "will" or "-ed" — something so ubiquitous that it is practically impossible not to get it right (unless you're not a native of the language).
As I mentioned, the only reasons I find plausible regarding why somebody might use わ instead of は and other broken japanese is that they are trying to go for the effect, or they are not a native. Take "生で私わしてほしいの", for example: this doesn't make any sense in japanse, grammatically. If I had to translate the effect of how broken this feels, then it would go something "Raw do me as want", instead of "I want you to do me raw".
I really would like to know what was the original intention of the people who did this.