A constant feature of this season has been the background grumble of dissatisfaction. You don’t have to spend long on social media to see moans about the quality of play, the sense that everything has somehow gone backwards since the tactical focus began to shift away from the pure possession and positional football of the peak Pep Guardiola years to something more direct and focused on set plays.

And yet, as we enter the run-in, there appears to be a proper Premier League title race. There is an extremely competitive battle to finish in the top five and qualify for next season’s Champions League and, although Wolves and Burnley are probably doomed, there are four teams scrapping to avoid that last relegation slot with another three glancing a little nervously over their shoulders.

The two strands, of course, are not unrelated. The reason this is such a competitive season is that everybody is flawed. But this is how it’s supposed to be. The days of a Manchester City or a Liverpool reeling off win after win and accumulated points totals in the high 90s are over, and were a historical aberration. Whether it’s Arsenal or Manchester City who win the league, the likelihood is they’ll do so with about 85 points. Does that mean they’re worse than those champions who got in the high 90s? Perhaps, but the fact that it will probably take around a point a game to avoid relegation this season suggests also an improvement throughout the division.

It’s almost certain that at least one of the newly promoted sides will go down, but as a group they have managed the transition to the Premier League far better than for some time – and that too has to be positive for the league as a whole. It’s one of the reasons Tottenham, almost unthinkably, find themselves in real relegation danger. Their defeat to Arsenal on Sunday was their heaviest home league loss in a north London derby since 1978.

While that restored a five-point lead at the top for Arsenal, who have played a game more than Manchester City, nobody should think that the stutter is necessarily over. Mikel Arteta was clearly delighted. He looked a lot more relaxed after the game than he has for a while, speaking of a possible “turning point” and how his side had reset after the disappointment of drawing at Wolves on Thursday. His assessment should not be underestimated. At the same time, though, Igor Tudor, who delivered his first post-match press-conference in the Tottenham job with the self-restraint and deliberate calm of somebody delivering uncomfortable but necessary home truths, described Spurs and Arsenal as occupying “different worlds”. Beating Tottenham these days is not much gauge of anything.

Eberechi Eze and Viktor Gyökeres deserve the plaudits for their two goals apiece, and Bukayo Saka sparkled on the right, but it’s entirely possible, come the end of the season, that the most significant aspect of the derby will be regarded as the way, for the third league game in a row and the fourth in the last six, Arsenal conceded within five minutes of scoring. Had Spurs held out for 10 or 15 minutes after half-time, Arsenal might have wobbled; as it was, two defensive lapses had them 3-1 up after 61 minutes.

But there is no reason to have any great confidence in City, even if they have won seven of their last eight games. Saturday’s victory over Newcastle was another game in which their level dropped in the second half. Seemingly comfortable at half-time, City ended up, if not quite clinging on, then at least under more pressure than seemed warranted. Statistics are often what you make them: they have only won four of their last nine league games, which includes the improbable late comeback away to Liverpool. Guardiola’s City used to be a byword for control, but they’re becoming specialists in edgy ground-out victories.

There is, perhaps, an explanation: fatigue. The expansion of every major tournament and the revamp of the Club World Cup means more games, just as the big clubs demanded. But their greed is effectively acting as a handicap system. The better you are, the more games you play, the more exhausted your players are and the more injuries you get. The result is that the football is of lesser quality, but the differences in quality within the division have smoothed out to an extent. The current profit and sustainability rules (PSR), which will be replaced next season by squad cost ratio, make it difficult to expand squads to cope.

In the short term, at probably unacceptable cost, the outcome is balance and, perhaps, an old-fashioned title race in the Premier League in which stamina and nerve are the principal virtues.

• This is an extract from Soccer with Jonathan Wilson, a weekly look from the Guardian US at the game in Europe and beyond. Subscribe for free here. Have a question for Jonathan? Email soccerwithjw@theguardian.com, and he’ll answer the best in a future edition.