I think you fail to understand something. No one who likes what SAO actually is considers the anime to be "shit". The anime didn't "turn" into anything. It's a fantastic adaptation.
As someone who like the books , i think the anime didn't do a good job at it.
The change of time was done abruptly .. with so few transistions. Many Boss battles were ignored or reduced to effects gifs.
They cut a significant part of ALO ( but they can still put it in a oav ) but it's still a cut.
They did cut small parts of Sao.
They nailed some episodes properly , but some others were terrible.
They failed to explain plenty of things to put thing into perspective... such as yui and her habilities, why did oberon lose like a slime .. and plenty of other stuff.
Seriously the anime lacked plenty of things that help to understand and leave an impression of shoddy writing when there is stuff explained.
I like the music in the anime, ep 1-2 , ep 9 & 10 , ep 20 ..this is all.
The anime is sucessfull but it's IMO full of problems.
Most of the people I know talk about kinda small things like Kirito's mental monologues not making it in or the pacing of SAO. They're things that can bother fans of the original (and you generally get these complaints from LN readers for any LN adaptation), but I don't think it's anything that'd completely ruin a series. The people who were talking about it with me say that it kinda messed up Kirito's characterization in the anime, so who knows lol.
They did.