The sad thing is that it's not just the Top 3. There are literally a handful of other players born in the 80's with better performances in majors than just about anyone born in the 90's. Who's the most accomplished player born in the 90's? Probably either Nishikori or Thiem? For sure, there's Wawrinka, Murray, Del Potro and Cilic. Even Tsonga and Berdych compares pretty favourably to anyone born in the 90's in terms of performance in majors. Edit: Forgot about Ferrer as well.