If I have to guess, they mean within US
Edit:
Here's a source that says they pay the same no matter if you're in the office or at home (basically), but it's limited to countries Spotify agrees you can be in:
> Location choices – we will also introduce more flexibility when it comes to what country and city each employee works from (with some limitations to address time zone difficulties, and regional entity laws in the initial rollout of this program).
- "Introducing Working From Anywhere" - https://hrblog.spotify.com/2021/02/12/introducing-working-fr...
- "Distributed-First Is the Future of Work at Spotify" - https://newsroom.spotify.com/2021-02-12/distributed-first-is...