I think many haters of SAO fail to understand the main point of the series as a whole.

Many haters and criticism surrounding the series cited Aincrad to be the best because of the concept, and I agree. The concept is amazing.
But their argument is that since Aincrad Arc

ended in just 14 episodes, the potential of this concept was wasted, and they should have gone all the way to F100.

Firstly there's a reason why SAO Progressive exists, to satisfy those fans who wanted more; an in-depth look at that world and setting they adore and love.

And secondly, they missed the point entirely

SAO was never about the game, it's about the characters, how they develop and their experiences in the virtual world changed their outlook on their lives. It's why S2 was "hated" because it was about the characters instead of the game

It's why the entire marketing of Alicization revolves mainly on the Rulid Trio, because the story isn't about the Underworld, nor about the RATH staffs and the girls, it's about them and their actions that made their story worth to be told.