Is English Football on a rise or the Rest of the World in decline?

Of all the 8 quarter-finalists of the Champions League 2016/17, only one team has been able to win their group this time around.
Barcelona: Group leaders
Real Madrid: Second in the group H
Bayern Munich: Second in Group B
Juventus: Second in Group D
Monaco: Eliminated
Borussia Dortmund: Eliminated
Athletico Madrid: Almost at the gates
Leicester City: Didn't even qualify

So what does that tell us about this year's competition?

The most obvious reason for the failure of these teams is the rise of English clubs at the moment. Man City is playing the best football in the world at the moment (along with PSG). Other English teams such as Tottenham, Chelsea, Manchester United and Liverpool are also in a way better form than last year. All the English teams occupy the top position in their respective groups which has never happened in the history of the champion league group stage.

Another big reason for this abysmal form from these teams is due to them being weaker than last year. Each team has either sold their better players or is going through a rough patch of form. Barcelona, although they're top of their group aren't playing as good as they did in the past and that is most;y due to the fact that they don't have Neymar at the left wing to run in at defenders. Real Madrid is currently going through a rough patch which is mostly due to a drop in form of Ronaldo.

Bayern Munich are in a transitional phase havings sacked Carlo Ancelotti after a humiliating defeat at from PSG. Their form have improved in the past month but a new manager comes in with new sets of ideas and methods which need time to settle in at the team. Juventus have also sold Dani Alves and Bonucci who were the backbone of the Old Lady. Atlético Madrid have fallen prey to the curse of a new stadium, which isn't actually a curse but more of a settling in the process but let's call it that it seems more fun. They're almost out as there is very less chance of a Roma loss to Qarabag along with an Atletico win over Chelsea to happen. Dortmund are surprisingly playing poor at the moment given the fact that they're always competitive irrespective of the quality of the squad (that Yellow wall certainly helps them at home).
Monaco have seen the biggest turnaround of fortunes of any above-mentioned teams. They've almost sold their entire first team with a couple more players to go after this season. The likes of Mbappe, Bakayoko, Silva, Mendy were sold for a more than handsome amount but that decision has backfired badly for the club as they got eliminated in the group stage itself, even though the group was fairly easy. As for Leicester, they were indeed a one season wonder.

What to expect?

As far as the form and squad quality is concerned, Man City are doing quite well and would be a contender for the big prize itself as the season progresses. I think Real will soon bounce back from their surprising bad form given that they made history by winning back to back Champions League last year and were the title favorites this year as well.
The teams among which the eventual quarterfinalists of Champions League 2017/18 will emerge are:
Manchester City
Manchester United
Chelsea
Tottenham
Barcelona
Real Madrid
Juventus
Napoli
PSG

This really looks like the Year of the Elite Clubs at the moment!