Benefits for s2 on Play generation hardware

As the story goes, I was on s2 when it launched and then the whole app fiasco happened and I was lucky to only have 1 speaker not support S1, so I replaced the speaker with a stereo pair of play 5 gen 2’s ( what an upgrade it was btw) I have somewhere north of 11 speakers. I was immediately relieved to have all my legacy features like LAN commands for automation work and a faster response time on local media on a local NAS. One of the things I did miss was high fidelity audio , the s1 app if it supports it doesn’t have a badge and I’m unable to test it in a scientific manner to ensure I’m not biased. Though it does support FLAC16 but again no indications in the app, recently I saw that Spotify is now supporting lossless audio. Also heard rumblings of adding fronts to surround.

Yesterday I was replacing a play 3 in my system with another play 3 I got off eBay, and for kicks I set it up in S2 and tried getting it going and noticed all the things that I was expecting from s2 didn’t work as expected, Spotify would not allow lossless. Is this a new speaker function and not available on the Play Generation? What are the benefits of switching from S1 to S2 with older hardware?