Hello~
I'm actually really exited to answer this question so here it is~
The use of social media has had a large impact on peoples writing. Although many people have been writing more, their writing had gone a bit down hill. People are not particularly focused on using punctuation and proper spelling when they aren't being graded on it. So in short summary, peoples writing has gotten worse spelling wise, grammar wise, and punctuation wise.
Hope this helps! Have a blessed day/night~
Ary~