Froome was the second pro cyclist to break his femur this season. The first was Nathan Earle.
Earle returned to (proper) racing 110 days after his crash. The Saitama Crit is 137 days after Froome's crash.
Actually, his first race after the accident was about 130 days later. But your point is taken. Earle seemed to have a somewhat similar accident, in that he crashed into a barrier, though it was one of those low corrugated metal ones, not a brick or stone wall. I don't think he suffered additional injuries like Froome, though, nor lost a lot of blood. OTOH, it's noteworthy that Earle was still recovering from a previous accident at the time.
But what we don't know is whether he's really been the same since. In 2018, he won 107 PCS points, 34 of them coming beginning in August. This year he had 43 prior to his accident in early April--comparable to 39 he had at the same time last year-- and only 15 since, after returning to racing in late July. That may not mean anything, but at the very least, I don't think anyone can say for sure whether Earle is back to 100% yet.
For another example, Luke Rowe returned to full racing just 6 months after breaking his leg in 20 places.
Rowe broke his tibia and fibula, not from a high speed crash into a barrier, but from jumping into a creek at a party. It was a simple fracture, i.e., the skin was not broken. Not to dismiss the seriousness of it, but recovery time from a fractured tibia or fibula is typically faster than from a broken femur.
Was he affected? He accumulated 322 PCS points in 2017, and that was with his season ending with the accident in early August. He won about 300 points in each of the previous two seasons. Though he returned to racing in February of 2018, he produced only 105 PCS points that season. This year, which began a year and a half after his accident, he's currently at 283. It appears he needed more than a year to return to his previous level.
He's back on the bike, but that doesnt mean he has recovered. His biomechanics will be altered probably forever and he will have lost muscle.
I would think so. I can't forget Beloki, who like Froome, suffered additional injuries to a broken femur (wrist, elbow). He did break his femur in two places, which I would think would be even more difficult to heal than a single break. In any case, while he returned to racing the next year, it was another year after that before he completed a GT, and he clearly was never the same rider again.
Every rider, and every accident, is different, but I would think Beloki would be a better comparison, not only because of the multiple injuries, but because he was an elite rider, who had more to lose, performance-wise, than Earle or Rowe.