Nice thread. My experience has been a mixed one but its gets better with time. I listen to apple music at resolutions16/44, 24/96. For mobility and listening on headphones via mobile phone or a portable headphone dac+amp on the go, lets face it any music service with 16/44 and above resolution is a dream come true.
An example of Alan Parsons album. The day I saw it labeled lossless, heard it on my headphone rig and was totally underwhelmed. Muddy. It sounded like hearing a cassette with the tape deck head dirty. Over time this album became better. They may have tweaked something at the backend or are streaming a another master/source. In the interim I upgraded my phone software too so who knows what made the difference. What I noticed was there were multiple versions of an album sometimes which sounded different.
A few other classical albums sounded good on streaming, just about on par with the cd equivalent. So no complaints there. Yes I can hear differences for the better in various albums as the service picks up momentum and phone softwares get updated. Trust me, I have begun to update my phone software only because of apple music

I guess the service's are optimising their streaming sources and end user software as well.
Should take some time for them to get to and stream the whole catalogue with the best source material. I guess thats expecting too much right now as well.
In some cases there are settings in the software which say “Auto” for streaming resolution which I turn off. Who knows if the software is auto downgrading a stream due to bandwidth constraints intermittently ?
Physical media have their own charm and will play consistently as long as they are maintained well.
To me streaming services are a huge convenience and a blessing but not a replacement for my physical media. Maybe in the future.