Difficult to compare. Federer had brutal competition all throughout the 2000’s while Djokovic achieved his stats mostly by feasting on mugs, the old, and clay courters
This isn't far off. Novak has had no younger great player, competing with him for the top prizes, period. One can't count single major winners like perennially injured Delpo, or otherwise impaired Cilic.
Federer has had at least 2 great younger players continuously since 2005 and 2008 (some might say earlier, but I only count from the time they won their first major), if you don't count 3 time major winners Murray and Wawrinka. I'm almost sure that Novak will not be able to endure a younger great multi-slam winner once he arrives.
Think about like this. How much more would Roger have achieved without significantly younger RAFA and Novak. How many majors? How many Grand Slams? How many Masters, how many whatever? This is the advantage Novak has enjoyed.
Of course it isn't Nole's fault that we have no slam winner under 31 years of age, and there is no doubt he has performed awesomely, but it makes it very difficult to compare their records. By the way, RAFA, and Roger to a lesser extent, have also enjoyed the fact that there have been no major winners under 31 years, but Novak being the youngest, and RAFA a year older, have been positioned to take the most advantage of relative weakness of the twenty-somethings through the two thousand-teens...
Respectfully,
masterclass
