The RF2 BMW DTM car is based on a car that was never actually built, because the new DTM class 1 was scraped before it raced.
DTM changed to GT3 regulations in 2021, with completely different engines.
So the comparisons between those two vids aren't valid.
Here is a vid of the actual engine that was supposed to be used: the BMW P48 2.0L turbo.
It sounds exactly the same as the RF2 version, although the real one is using a slightly lower rev limit.
I think the rf2 version sounds very good, one of the best if not the best sounding official cars.