I'm 49 and I've watched football through the late 80s to now and I can confidently say football now is at its worst level and if you look at the traditional powerhouses in both club and International football they are far from their vintage best
I think the Premier League is a perfect example of modern football.
Football in general has become more athletic (due to modern science), and the game is faster than it's ever been. There are far fewer poor players playing in the top flight now, and that means the gap between the top players and the bottom players is smaller than it's ever been.
So where you'd have Henry blitzing players, now most players are fast (just not Everton players). Same when you'd have a Drogba bullying defenders, now they are all physical, so it's a more even battle than it used to be.
Because the game is faster than it's ever been, and it's also more tactical, you see less players like Zidane etc. because they are not given the time and space they may have had previously. Most players are technically good now as well, so again the gap between the top and bottom is much smaller. They can all kill a ball dead and do skills.
In the Premier League it means the gap between the top teams and the bottom teams is smaller and it's turning in to a league like the Championship has been for years. This has been helped by the TV revenue dominating most club's revenue.
In other nations you'll still see one or two teams be able to easily dominate (as their revenues will dwarf everyone else in their league) and on a Global level those teams can compete, hence why the Champions league frightens our ## manager. But in the lesser European competitions, English sides have dominated this season because they likely dwarf those other clubs in terms of revenues etc. and therefore can afford better players, coaches etc.
So I don't personally believe the level is worse, I think it's higher than it's ever been, but it's hit a level where athleticism is far more dominant than it ever was, and tactical input from managers is far more detailed than before. So the game is a different watch to what it used to be.