Nope. One they weren't better and couldn't have been too. Teens is bit early imo to have that kind of consistency with that playing style. What is surprising is they still look in quite good shape. I still don't think they can last at top as long as Fed but if this Wimbledon is an indicator, they can last couple more years.
Becker won 5 out of his 6 slams before hitting 24.
Borg retired at 25.
Nadal's after 2014 FO up until last year was shit on a stick. Didn't make it past the QF at any slam. Djokovic since 2016 didn't make a slam SF up until this Wimbledon.
So no, they aren't better and neither is Federer who won 3 slams in the last two years.
Both Djokovic and Nadal are slowing down and the match yesterday was level or two below the one in 2012 AO for example.
The competition since 2013 was really poor. You have Anderson making 2 slam finals, Nishikori, 31 years old Ferrer, Thiem, Raonic, etc etc.
Murray has been injured for most of the time, Federer is also quite over the hill, yet the old guard is constantly making deep runs at slams because the young guns are just not there. The Dimitrov, Raonic, Nishikori, Cilic generation weren't good enough and the young lads like Thiem and Zverev are pretty useless at slams so far.