Even if Sonos went belly up you’d still have airplay and tv/line in, along with direct control from stuff like Spotify (until Spotify inevitably change their protocols). But I don’t see airplay ever quitting until the hardware does
Yes, because Apple is a company known for their commitment to longevity and compatibility.
> tv/line in
Many of their devices don't have any line in ports.
Can a person configure the wifi settings for an Airplay-capable Sonos speaker without the Sonos app?
Most Sonos speakers do not have any inputs, sadly.