Yeah the ISS is where we're learning how to actually run a long term space habitat. Each station has taught us more about tons of things that happen here on Earth by removing the effects of gravity so that other forces with much smaller effects can be examined and harnessed. There are other ways we might have gotten this data but there's a lot to be said for having a person there to repair anything that's gone wrong or to change experimental apparatus instead of having to launch it all again.