If you mean, for example, disagreeing about whether a disc is M- or VG+, I agree.
For some reason, the situations I run into are usually more blatant - disc's graded as M or like new that arrive with obvious scratching and or scuffing. There are still quite a few reputable sellers out there but if I buy from a seller that's new to me, I never know what to expect when it comes time to open the package. It does take some of the fun away from collecting.
Unfortunately, there is no grading system that can compel all sellers to be diligent/honest... not yet, anyway.
And we haven't talked about the rising prices ! I don't know if this affects vinyl but used cd prices have really gone up.