I don't know what retirement laws are like in other countries. In mine (depending on your profession, of course), but for normal people, it would be 35 years of contributions to the government (deducted monthly from your salary), plus 65 years of age.
In other words, you need to be 65 years old and have contributed for 35 years.
It used to be easier, but retirement laws have changed recently.
And since this game has always been a retirement plan for the developer, I believe that perhaps the retirement laws have changed in your country as well. Forcing him to reformulate the entire game, so that it matches the time remaining until he can retire.
Maybe that's why the game was reformulated, since Pre-tech was moving too fast, and it would go against the time he needed to retire.