Personally I think that people should stop saying that Steve should or must stop for his own good. Unless you are inside his head and his body, unless you have up-to-date intimate detail of his thoughts and feelings, then it is only your place to speculate or offer opinion, just like sports pundits or political commentators.
After all, we all know best, don't we?
Please, stop bickering, stop petty point-scoring: let Steve decide. Be supportive or destructive if you wish but we all value our autonomy, our ability to make decisions for ourselves.
There is no sense in my mind that there is any failure in Steve's attempt. He's still riding nearly a year after starting in spite of an accident. He's clocked up 100,000kms and counting. It's an attempt, not a guaranteed shoe in.