Attached below is a link to an interesting review article from InputMag magazine. It seems to be a fairly honest and and true review, with comments both favouring positive and negative points with the S21u.
I haven't posted this article to restart any complaints from this community, between the processing on Exynos / SD888, or to favour one way or the other.
My fairly amateur opinion is that the camera is not perfect yet... but continues to improve. Some photos make me stunned of the quality, although some darker exposures show artefacts and issues. Also video and super stable mode generally come out well, but again sometimes there is a minor issue that isn't great observed during playback.
Overall the S21u is by far the best camera I have owned in a phone, and I am therefore very happy with this performance. I still think that Samsung will strive to improve the processing on some of these issues...