Update - I sent my resignation today, and the company immediately reposted my job with a 40% salary increase.
Title says it all. I'm the person that posted a little over two weeks ago about my boss asking me to "please refrain from frustration during admin issues".
Immediately after sending my resignation, the role was posted with an increase from $28 an hour to $40 an hour. In terms of annual pay, that is a raise from 58K to 83K. While I know I was never valued during my time there, this jump in pay really takes the cake.
I have loads of respect for fellow EAs, but after the experience I had at this job, I anticipate that I will transition out of this line of work altogether and go back to my previous career. I have temp work lined up for after I'm back from traveling so I know I'll land on my feet.
I wish nothing but the best for whoever takes this role next. Maybe he'll strike gold with his fifth assistant in three years. Or maybe not, idk much about pattern recognition.