Larian is already rushing the game to you because they moved the release date for business reasons to beat Starfield. So you will already see a degradation of quality as they need to do the work of 2 months in 1.
And a preorder always means that you buy something unseen. And for that risk to be worthwhile the incentive should be quite good. A digital art book, an OST you can likely get from youtube anyway and a few ingame skins and items are imo not enough. Especially also with all the questionable decisions about multiclassing, respecs and hirelings, attributes and race balance (humans), their general focus of "go evil or go bust" ect. come to light which makes buying BG3 unseen a bit questionable in my opinion.
Fortunately we can all make our minds up about what we want to do. Personally I already bought the game unseen years ago, and have neither regretted it nor expect to, despite having some questions and concerns about more recent news.
But if people have their doubts then yes, it makes more sense to wait and read reviews and get feedback from early adopters.
