The assumption that aliens, if they exist, must necessarily be more advanced than humans is not necessarily true. There are several reasons why aliens, if they evolved from a different planet, might not be more advanced than humans:
Different starting points: The development of life on any planet would be influenced by a wide range of factors, including the planet's environment, its resources, and the unique evolutionary path that life took there. As a result, the starting conditions for the evolution of intelligent life on different planets could be vastly different, leading to different outcomes in terms of technological advancement.
Time and age: The universe is estimated to be around 13.8 billion years old, and there could be planets that have been around for billions of years longer than Earth. If intelligent life evolved on such planets long before it did on Earth, they could have had a head start in terms of technological advancement. Conversely, there might also be planets where intelligent life emerged much later than on Earth, making them less advanced.
Different evolutionary pressures: Evolution is driven by the environment and the challenges that organisms face. The evolutionary history of an alien species may have been shaped by different factors than those that influenced human evolution. Their biology, social structures, and ecological context could all contribute to differences in technological development.
Intergalactic factors: Even if a civilization elsewhere in the universe had a head start in technological advancement, factors like catastrophic events, self-destruction, or lack of interest in space exploration could limit their potential to explore or interact with other civilizations.
It's important to remember that the concept of aliens is purely speculative at this point, as there is no confirmed evidence of extraterrestrial life. As such, any discussions about their potential technological advancement remain theoretical and subject to a wide range of possibilities. Scientists continue to search for signs of life beyond Earth, and future discoveries may shed more light on this intriguing topic.