Hasn't corporatisation/marketing of music always 'changed the sound'? I can't even think what non-commercial music would sound like, unless it's classic folk tunes, and even then...
Every part of the world has it's own local sound, although perhaps less and less and less these days.
There's always been "music people play to be social" with a line from that to "music people play to make some extra cash at the local shindig" which is the essetial core of commercial music - if you want the money you have to appeal to the crowd.
Anyhow, for what it's worth - back in the day we'd drift into the nearest big town once a month or so and typically have an all night get together | jam session with these people (and others) .. it's classic folk but particular to a specific bit of the world:
