not if you compare it to any other generation....like ever. not saying those guys aren't talented, they are, and i particularly like what i've seen from goffin, even if he is a bit lightweight. however, these guys are pretty much in the 20, 21 age range and have barely had a sniff of a chance of winning a slam, reaching the top-ranked places in the game, etc. they are already waaay behind most of the top players throughout history in the open era, and certainly by 23, the vast majority of first time slam winners are one (or two) hit wonders, with the exception being lendl. but like murray if he were to win a slam soon, lendl had proved that he belonged in the upper echelons of the game already.
what i mean is that in any other generation within the open era, the players who go on to have very good slam-winning careers have been at the very top in general between 17-21. there is no indication that the generation to which you refer will be in that bracket. they may surprise me, but i can't really see any of the players that you mentioned (or the likes of berankis, etc) becoming multi-time slam champions unless the generations that follow them are even worse. tomic perhaps has shown the most to me, and is still only 19, so i guess i'd go with him if i had to guess at one of these guys to become a huge success. but i can't really see it atm. by the time fed, djoke, rafa and murray are away, these guys will be in their mid-late 20s and it might be too late by then.
That 'good' was supposed to mean 'decent'
If we stopped seeing teenage girl sensations anymore, since 2007 (Nicole
), I guess we won't see boys cracking the top at young ages either, so I think Dimitrov, Tomic, Harrison & co are doing just fine.
Considering Roger, Rafa, Nole and Andy won't be there forever, I expect these guys to dominate grand slams for a few years, especially given' the quality of younger up and comers.