It might be tempting to see some tidy symbolism and greater significance in Novak Djokovic’s loss to Jannik Sinner in the Australian Open semifinals. The breakthrough for the twentysomething Sinner, an up-and-coming talent who will now get to play in his first major final, against Daniil Medvedev on Sunday. Then again, that was the sort of passing-of-the-torch oversimplification some folks found in Djokovic’s loss to another kid, Carlos Alcaraz, in last year’s Wimbledon final.