Why YSK?
The first person who typed “should of” probably heard of it in real life that was meant to be “should’ve”, they typed “should of” online and readers thought that it’s grammatically correct to say “should of” which is in fact wrong and it became widespread throughout the years on Reddit.
I hope something could start to change.
Shakespeare did not “make” changes, he’s just a very good record of changes that had taken place.
That us just incorrect, his plays marked major shifts in the style of writing for the english language, many writers after him adopted his style and the new mechanics he was making in his plays.
https://online.maryville.edu/blog/william-shakespeare-influence/