As a delivery format, yes.
anyone out there doing serious multichannel sound for the formats you mentioned won’t care about disc space, CPU cycles or compressing anything. Why would you need to?
I don’t agree with you. As FLAC, lossless DTS and Dolby are delivery format, not production format. I consider that I do “serious” (for me, not equal to money) multichannel work, and I would enjoy the disc space saving from the get go, rather than only at the end when I archive the project. Maybe it’s because I work on a laptop…