There’s a lot of talk about 5 year old systems being dropped but those devices actually date from 2005 connect amp(zp100 at the time), 2006 connect (zp80 at the time) and 2009 play 5 (zone player s5 at the time).
How many of us have a 2005 computer that you expect to run the latest os on?
The platforms that are being dropped are based on 11-15 year old platforms irrespective of when they were purchased.
Also we need to consider that it’s not simply Sonos making this call, changes made by the bbc, Spotify, deezer, tunein all have a part to play and require Sonos to release updated software.
I can remember when the bbc made changes to its streaming services and listen-again functionality was lost for a month or two, totally out of Sonos control.
There comes a point in all computers lifecycles where it’s no longer technically and / or commercially viable to continue support, 11-15 years doesn’t seem unreasonable to me.