Assalamu alaikum wa rehmatullahi wa barakatuh
It is He who created for you all of that which is on the earth. Then He directed Himself to the heaven, [His being above all creation], and made them seven heavens, and He is Knowing of all things.(2:29)
Note 2 important points according to the verse:
Modern astrophysics states that once the planets and galaxies were formed,the universe was homogenized.
The large structures were formed. Stars were organized into galaxies, which in turn form galaxy groups, galaxy clusters, superclusters, sheets, walls and filaments, which were separated by immense voids, creating a vast foam-like structure sometimes called the “cosmic web”.
After that there was a period of End of greatness when the lumpiness of the universe was ended,the universe was homogenized.
Now see the diagram given below.
After the Big bang, the universe was there in an unorganized form.
Then there was a period of slow expansion whereby the high density planets were formed.
After that there came a period of accelerating expansion which led to the organization of the heavens into 7.
The order mentioned in Quran is totally correct.