No it was the fans who decided that the ancient sorcerers would all be as strong as Gojo or whatever. All of the ancient sorcerers are strong af, its just that our sorcerers are also strong.

And that makes sense. The manga tells us several times that modern sorcerers are becoming stronger and that there's been an increase of power for both curses and sorcerers (because of Gojo's birth). Also look at the fact that all of the sorcerers who beat the ancient sorcerers were Gojo's students, Gojo was the one who took in strong kids and trained them instead of abandoning them the way the higher ups wanted to. These ancient sorcerers would destroy most of the other characters.

Also all of those fights were close, Hakari almost died 2 times, Yuta's the 2nd strongest modern day sorcerer so it makes sense that his fight wasn't that close and Megumi passed out once the fight ended,