I'm going with what you mentioned as you said you "disagree that a prior injury indicates future result", which is false. Regardless of whether there were 2 completely separate injuries or a flare up of a previous injury, we know he's had at least 1 surgery in his past. Having had an injury that required a surgery, even once it's fully healed, indicates risk for future injury in that anatomical region. That's just objective, orthopedic knowledge that that can't be argued about being injury prone. I'm just being finicky on a semantics issue regarding the difference between how we feel as fans compared to orthopedic data.
But really it's all moot and doesn't need to be dwelled upon because we can't actually predict the future and all want him to stay healthy for the sake of the team.