Fairly recent digital done shows like 2009 maybe or a few years earlier done in 480P anime. Yeah those are usually upscaled by some company if they even bother to do Blu-Ray for them at all and just don’t have one DVD release. or they reissue them on DVD. Or put them up on a streaming site.

I’m thinking of Haruhi Suzumiya season 1 that was animated in SD. And I do have the Blu-ray. You might be able to trick me into thinking its 720P because it’s not the worst upscale but it is definitely not 1080P.

Even the alleged to be 2k master of the film in 1080P looks to me not very highly detailed and a rather low ish bitrate on the disc. If I was again told it was animated in 720p I would believe it.

Those are just one example.

There are cases where an upscale looks worse than the DVD like Lucky Star from Kyoani.

Or Shakugan No Shana from J.C. Staff.

And there are certainly decent examples but imperfect like the 4K of Nadia Secret of Blue Water. Which is from a film scan and not an upscale but had been subjected to DNR and has less detail than the previous blu-ray.

Most people are happy with the result of increased contrast and better colors. And being faithful to the animation cels and won’t be upset over the film grain being gone.

You also have really tremendously good remasters only knocked down a peg or two by the use of DNR like Urusei Yatsura original not remake tv series. Dirty Pair TV series, movie less subjected to DNR but still applied. Plus old gags removed for copywrite reasons ever since the remastered DVD. And need the old DVD or laserdisc for those scenes.

Ranma as well good film scans. Most of the Rumiko works. I forget if they redid Mason Ikkoku. Or the Rumik World. But certainly, the films of Inuyasha had good scans. I forget if the series did.