I even played Strat-o-Matic baseball by mail when I was a kid! We'd fill out our rosters and managerial instructions then mail them off to our opposing team's manager. A week later I'd get the results back in the mail. Hard to believe such a relaxed pace.
Clicking the OP link I get a warning page from my ESET AV:
"Potential phishing attempt. This web page tries to trick visitors to submit sensitive personal information such as login data or credit card numbers."
I started coding at 22 years old out of college and am now 58. I've resisted the pressures of becoming a manager my entire career and have had no regrets. Recently I turned down yet another manager role for all the reasons you gave and couldn't have been happier. Management at my place understands my career plans and have been accommodating. I plan on retiring in 10 years but know a lot can change between now and then so if my current job becomes unbearable, I'll leave and take on freelance coding projects. I will never become a manager.
I can't stand when someone answers a question on SO by first admitting they know nothing about the subject then take a guess with an answer. Why bother answering if you don't know the subject?