Kakashi is a unique character in the Naruto series. Kakashi sure is powerful when the audience first encounters him. However, he is nowhere near the raw power of the kages then, and only had a single sharingan.

He had mastered a thousand jutsus, and had considerable skill in taijutsu. As the series progressed, Kakashi as a character was developed better than most other characters, excluding the two protagonists Naruto and Sasuke.

Kakashi never relied on raw power to overpower his opponents. His battles were always based on skill and stealth when he was in the ANBU, and they continued to be an active part of his strategy even after that.

Most of the other hokages before and after him would beat him on a matchup of raw power. Kakashi does not have a sizeable chakra reserve, nor does he have any powerful signature moves that could blow stuff up and rip them apart.

His chidori is a concentrated, accurate jab, not a powerful attack. One could see its relative accuracy and penetrating strength when Naruto and Sasuke fought against each other on the roof of a hospital. While the rasengan ripped the water tank apart, the chidori penetrated well into the tank, but failed to destroy it completely.

Thus, where Kakashi triumphs most of his adversaries in are the domains of skill, technique and strategy. Kakashi usually combats people with a partially established plan, with immense skill and technique to back him up. He never uses his strength to overpower his opponents, unlike Naruto or Sasuke. This makes him seem less scary in the anime.

Kakashi’s father and teacher, both of them were legendary warriors who implanted in him, the importance of skill over power. His feats were always skill based, never power based. His reliance on his skill made him evolve his techniques over time to combat powerful characters like Obito and Pain. Kakashi found it hard to battle Pain because he would not battle him one-on-one and also Pain had more brute force. Even then, he managed to somehow make it alive and also saved Choji.

Kakashi has his funny moments, but was far from a funny character. The ANBU was analogous to a special forces unit. Modern special forces are scary as hell, in real life. They are the most elite troops a nation could establish with the people trained in almost everything there is to train for in the world. And even then, special forces are highly disciplined and coordinated, with some of the highest success rates.

This means that if Kakashi has been established as your enemy, and the man’s coming after you, you can be sure as hell that he would probably succeed in accomplishing whatever he was trusted with - meaning you probably are going to see your body go limp as your head rolls away.

He at one point in time, had the mangekyou sharingan. This means that Kakashi could very well muddle up one’s perception of reality and use that in his favour too. A sharingan-less Kakashi is still ANBU level Kakashi with more years of experience in stealth techniques than almost all characters in the anime. An assassin is always scarier than a brute warrior. Kakashi will always be scarier than Naruto or even Jiraiya, for that matter.

You can see Kakashi’s official stats and know what I mean.