If you're talking about relative strength (the only thing that matters) then the PL simply isn't at its strongest ever level. It was stronger from 04-09 and from 76-84. In absolute term its the strongest ever but that's because tactical and fitness advancements have taken the game beyond what previous eras could cope with if you transplanted them into this era. Such a perspective is worthless, however. Players and managers should only be judged by the eras in which they operated. When Ferguson had his greatest period as United manager the depth of competition for the title was undoubtedly stronger. All of the top PL 4 appeared in a Champions League final in that era United x 2, Liverpool x 2, Arsenal & Chelsea x1 in a 6 year period and it was no surprise when they made the final like when Spurs did last year. Liverpool won the CL whilst finishing 5th in the league. In the 76-84 era 3 different English sides won the European Cup in 7 out of 8 seasons.
As for Klopp, his style that has finally got him success in England more represents that old school British football seen in the 76-84 era: only Sheffield United and Burnley have played more long passes than them this season and only Bournemouth have scored more set piece goals.
It's funny how things turn out, now tiki taka is dying and being replaced by long passes and 'vertical' football' but then as Sir Alex always said when Guardiola came on the scene 'football always goes in cycles'.
Well thats it, style of plays have cycle they don't essential die out in itself. Usually this comes down to also when the style comes into play and if its counterpart is there at the time or not.
In football we have 3 philosophy in terms of style of play:
1. Catenaccio - The school of Helenio Herrera and today largely used by managers like Mou, Simeone, Conte, Allegri with different variations.
2. Total Football - The school of Rinus Michel and today largely used by Pep, to an extent Tuchel and Sarri with different variations.
3. Counter attack/pressing - The school of Arrigo Sacchi and today Klopp and Jardim Monaco in the league winning season were variations of it.
Catenaccio:
Is largely based around defensive set up, its created to take the piss of opposing teams and making it difficult for them to break through and while watching them suffer and in hopes you can capitalize on them when there guards are down, low morales which will force mistakes.
This style of football requires players with high intensity, great defensive awareness and capabilities, mental strength to constantly be able to soak in pressure. They don't require to many flair, offensive type players, Herrera had Luis Suarez (Spanish), Mou at Chelsea had Drogba, at Inter had Sneijder and Milito, Simeone, Costa and Greizmann.
Total Football
This is the opposite of Catenaccio, its a full out attacking system that revolves around dominating and controlling the game. This is style that requires a lot of patients, it set up to create numeric superiority, while putting players in 1 v 1 situations.
This style requires highly intelligent and technically gifted players, that are also good at dribbling, as well as GK and CB that can play out from the back.
Counter Attack/Pressing
This is largely a mixture of both while it emphasis on both attacking is the main outlet. Sacchi Milan wasn't just good at attacking but his defense was one of the best of all times, even while Klopp offense is great defense is still a big part of his team too. This is a style that doesn't really require creative from midfield, hence neither Sacchi or Klopp have technically gifted midfield, both midfields were work horses. Its about pressing and winning the ball then go straight out attack, if you have to soak in pressure then hit them out the break quick.
This requires strong defensive core with workhorse players on both offense and defense, as well as a strong capable attacking group of players.
Now each of these style counter one another:
Total Football > Catenaccio
Catenaccio > Counter Attack/Pressing
Counter Attack/Pressing > Total Football
It doesn't mean they can't beat one another, but largely your best chances to win is by using the counter.
Total football with its gifted players, intelligent movement, numeric superiority, dribbles + putting attackers in a 1 v 1 situation becomes a big issue for Catenaccio base teams.
Catenaccio makes life difficult for counter attacking based teams, because they form blocks and give very little space to those counter attacking players and they themselves don't want possession and counter attacking teams aren't build to keep possession and dominate the game which impacts them.
Counter Attacker teams feast off the space high line, possession, total football type teams leave, this is were there counter attack is most effective and deadly to take these teams a part.
Some example:
Sacchi struggled domestically a lot due to the fact that Serie A was a very defensive oriented league, despite the fact he had one of the greatest squads in the history of the game, but when he meets his counter parts every day it provides life to be a bit more difficult domestically.
Klopp has been able to steamroll teams because he's yet to come up against a defensive juggernaut, with the decline of Atleti and Juve its time for counter attacking teams to rejoice.
Carlo Napoli also made life difficult for Klopp Pool when they shut up shop, despite Carlo not being defensive juggernaut type.
Pep record against defensive managers, Mou/Simeone/Allegri/Conte --- Wins 17 Losses 9 and some draws in between
Pep best CL campaign arguable since post Barca was his last season at Bayern when he landed Juve and Atleti (defensive teams) were he played Kimmich and Alaba as CB and lost an away goal rule.
Klopp despite having inferior squads compared to Pep has a better head to head, matter of fact I believe he's the only managers right now who has best Pep the most and with a postive W/L.
Pep CL run since post Barca, loss to RM on the counter, loss to Barcelona with MSN on the counter, loss to Monaco on the counter, loss to Pool on the counter, loss to Spurs once Kane went out this allowed Son and Moura to hit them on counter.
Pep up until this season went 3 games undefeated against Klopp and his teams average possession was around 50%, he gave up total football in order to beat him, which saw City win the league last season.
When Pep Barcelona came around we didn't have team like Klopp Dortmund/Pool, Jupp Bayern, Carlo/Zidane Madrid, etc that would've troubled them. Now we have counter attack football returning due to the fact defensive juggernaut have declined and who knows when next will see another Inter (09-10), Atelti (14-16), Juve (15-18).