I've been saying this for months on here, some people have said I'm wrong. As I always use as an example the 2008/2009 United team contained EVDS, Evra, Ferdinand, Vidic, Carrick, Anderson, Scholes, Fletcher, Ronaldo, Nani, Park Ji Sung, Rooney, Tevez, Giggs, Rafael, Berbatov, Welbeck, O Shea, and Jonny Evans and were never destroying teams like Liverpool are now and in fact Liverpool beat that team 4-1 at Old Trafford. When you look at the teams Chelsea, Arsenal and too a lesser extent City have had and they never achieved what Liverpool have done.
But what I've have always found suspicious is as you say I can kind of understand with VVD as defenders get older they develop more experience and get better, but it's very strange that players like Robertson and TAA have miraculously become world class almost overnight. Milner and Henderson are probably the most suspicious, Milner had peaked when he was at Villa and his first few years at City, he wasn't even considered that good in City's average 2013/2014 season, to all of sudden become world class towards the end of his career is strange, Henderson wasn't just average he was dire and he's turned into a world beater. Salah somehow became a world beater overnight, but then in his second season he look pretty average. Firmino was a good player, but was never the world beater he is now, same with Mane.
Also they were pretty poor in the early rounds of the champions league last season, yet scraped through. Spurs got to the final, but they're still recovering from playing some many games and all the injuries that came with it. They've somehow despite making very few signings and still having a relatively small squad been able to come back even stronger with no sign of fatigue. It's one thing for a team to be good, it's another thing when they seem to be far fitter than the opposition. The fact that Barca rested all 11 players after the first leg for their league game, yet Liverpool were able to go to Newcastle and still come back to beat Barcelona really should of had any sensible persons spidey sense tingling. It's not even about bitterness, I'm honest enough to say they deserved to win the league in 2009 and 2014 and were unlucky then. Evertonians are generally pretty knowledgeable about football and we know when a side is fantastic, this Liverpool team aren't.