It is a situation where having a higher quality scan of the film shows both the clear parts clearer and thus blurry parts seem blurrier. They did try to use AI to sharpen up some of it. To varying degrees of success.
I'm certainly not going to defend anything as I had no involvement in this remaster, but there is a myriad of things that can cause portions of animation cels to not be captured perfectly clear. And since the assets have all been sold off to collectors, the odds of recapturing the work from scratch are all but impossible.
This is arguably, the closest to the original intent of the creators that DYRL may ever be.