The talk of changing of the guard has been happening for at least 5 years, but the Big 3/4 clinged on and scooped up more majors between them, their superiority seemingly insurmountable. But I think this is it; the close of one great era, will hopefully bring the dawn of another, with alcaraz looking to lead the pack. I see Nadal and possibly Murray retiring next year and Novak a couple years after, depending on their health and hunger to stay competitive. The GOAT debate is always controversial, but for me, Federer, with all he's achieved on and off court, the way he's beautified the game, transcended the sport, is the GOAT.
Let's hope he stays in the sport: talk of coaching young Swisse players, commentating, exhibition/charity events abound. But no doubt some much needed rest and family time.