BD-R’s have scratch resistant coatings and usually better protection against delaminating.
Discussion
I've never used BD much. I didn't think I've had a device with a disc slot since my Wii 😂 the only reason I know is from helping an audiophile friend rip his CD collection to flac when he had some old discs start to discolour & flake. Got him very stressed out.
CD data layer is at the top of the disk directly exposed to the environment