From what I understand, it is a very difficult job.
You have to take a battery of general aptitude and temperament tests and then they pick a couple thousand (out of 10’s of thousands) to go to a multi-month training assignment in Oklahoma.
In Oklahoma, 40% will wash out.
I almost became an ATC in the mid 80’s That sounds like what I went through. I took an aptitude test and went to visit a tower in Lubbock. They said more than likely, you would end up in a small tower like Alexandria, Louisiana or Fort Worth Center. Eventually, I went back to graduate school. I just wonder how my life would have been different.