True mate, especially the skill factor when you consider the cow fields that they used to play on. Modern pitches are like carpets in comparison.
What does annoy me is how modern footballers complain about fatigue so much and managers resting players. Granted, I know that it's a much quicker game nowadays and players need to run further and faster, but consider that we used to play 42 league games a season without the cup competitions. I think we had a season where we used only 15 players. Aston Villa only used 14 players when they won the league in 1981 IIRC.
For a good insight into why modern players complain about fatigue go and check out the famous 1970 Brazil world cup final. Look how little actual running the teams do. There's no pressing, and for long periods players are literally moving up the pitch at walking pace, standing still for ages, passing back and forth. It's like a completely different sport. Pressing was only really invented in the 70s, and didn't become commonplace until well into the 80s.
Even then there's just no comparison between now and even 20 years ago in terms of the amount of running players do. To put it another way, ask yourself how it is that so many top players back in the day smoked shitloads AND had serious alcohol problems, or at least drunk shitloads? A player simply can't afford to do that now. Look at someone like Johnson of City - a couple of years 'easy living' and he's almost dropped out of the game completely. 20 years ago he'd have been a star for them, fatty with alcohol issues or no, a la Paul Merson or Paul McCrath or even Neil Ruddock. Those kinds of players have disappeared from the game completely.
It's worth listening to top physios about this as well - it's physically impossible to stay at peak fitness when you play 3 games in a week, and every time you play at less than peak fitness you significantly increase your risk of injury, lengthen your recover time and then there's more chance of you getting injured next week etc etc. This can be managed to an extent - for example in 08/09 Torres and Gerrard didn't tend to press as much as some of our other players, and Torres in particular was often taken off in the last 10-20 minutes of games where the risk of injury is biggest.
Back in the day, you didn't need to rotate and you could play more games in a season because during those games you were, on average, running 2/3 or even 1/2 the distance. Tactically the game hasn't changed masses in the last 20 years but fitness-wise it's a different world.
Just for the record, check out the England cricket team at the moment as well. The sport on the whole still hasn't learned like football is, but look how fit, how seriously they take fitness, compared to even the Flintoff years, then compare that to some of the Aussie players. They aren't the most amazing talents, but their fielding, their consistency, their lack of injuries are obvious, and that's because they're taking fitness much more seriously. It's also an approach where I honestly think they are becoming the most fitness focussed team in cricket, and in a few years that will make them the best team in world cricket. Another great example would be Tiger Woods in Golf, or even Lee Westwood who's rocketing up the rankings has gone hand in hand with him swapping burgers for the gym.
EDIT:
A last couple of points:
You see it really clearly around christmas, teams looking like they're running through treacle - that's fitness.
Last of all, is it really the players who complain about fitness? I haven't found that at all. Players tend to be desperate to play and say they want to and can play every match. Players actually tend to be stupid about their own fitness - they shouldn't be trusted, for the most part. It's coaches and physios, who in that respect know the players much better (ususally) than they do themselves, who moan about it, and rightly. There's a reason why most coaches back a winter break while players don't talk about it anywhere near as much.