I wonder if they are going to 'John Glenn' Yang Liwei. John Glenn, for those of you who don't know, was only allowed to fly one flight in the early American space program because they wanted to make sure at least one astronaut hero would survive and act as a symbol.
Yang Liwei hasn't flown since 2003. Could it be for the same sort of reason?
John Glenn flew twice. Also John Glenn wasn’t the first American in space. It was Alan Shepherd. Alan Shepard also flew twice.
Yuri Gagarin was also slated to fly again, until death of Vladimir Komorov, to whom Gregarin was a back up, caused the Soviet leadership to forbid it.
The only big name 1st in space person to never fly again, AFAIK, is Valentina Tarashkova, the first woman in space. But then she was easily the most under-qualified soviet cosmonaut of that generation.
I see Liu Yang, the first Chinese woman in space, will not suffer the same fate. She is slated to fly again on later tiangong assembly mission. So I suspect there is no imperative to keep Yang Liwei from flying again either.
It is not PC, but the reality is it would certainly look bad if a woman is risked again and suffer an accident, when the man is deemed too precious to risk.