1) You are making absolute statements about sound quality based solely on your personal experience which may or may not be limited. That is a mistake.
2) digital sound stage is not 2-D. If that is what you are experiencing see 1).
3) Compressed file formats be they lossy or in this case lossless do require additional processing on the streamer to decompress before streaming. That might produce different noise levels with some devices. So I can see where more compressed lossless flac might be at a disadvantage but results will still depend on how well the streamer is able to do its job.
2) digital sound stage is not 2-D. If that is what you are experiencing see 1).
3) Compressed file formats be they lossy or in this case lossless do require additional processing on the streamer to decompress before streaming. That might produce different noise levels with some devices. So I can see where more compressed lossless flac might be at a disadvantage but results will still depend on how well the streamer is able to do its job.