Because workers need 25 years of service AND to be of an eligible age before they can receive pension payments. At least for most state agencies. So even if you have 25 years of service you still aren’t getting your pension until you’re 68 ( age might be lower depending when you started).

I work in state government and while you do get something like 80% after 20 years of service you ALSO have to reach a certain age ( 68 years old) before you can start receiving the money. So in your example you could quit government at 46 and know that pension is out there waiting for you in another 22 years, but you’d still have to go work somewhere else in the meantime ti support yourself. I don’t know if the contract for T workers is different but I’d be surprised if it were.