Trackers like MilkyTracker, OpenMPT, and Famitracker are trying to mostly enable people who use trackers to continue writing music for specific formats (and the specific limitations of those formats).

There are much more modern trackers as well. As far as I know, the absolute state of the art is Renoise. There are some other alternatives like SunVOX.

The downside of the modern trackers is that you very much have to replay the songs in the tracker themselves, with all of the same plugins and settings. The older formats have lots of playback targets and tend to be very resource light for a very good sound.