The studies aren't reflective though as they take into account all players at all levels and they mainly focus on maximum physical performance.Only if you are talking goalies. Studies have shown the peak year of a footballer to be 27. If you look at most any squad you will find their average age to be between 26 and 27.
Squad average ages take into account economic valuations as well as performances so it's a bit more complicated than this. Traditionally, "prime" was considered 28-32 though I could see that getting a year younger due to more physical nature of football now. But the other guy's idea of prime being 23-27 is just fucking bonkers.