The length of the output is not the issue. The problem is that the output includes drums, voice, and several instruments already premixed into an accompaniment. What music producers really need are isolated samples of just a single instrument that can be mixed, layered and rearranged using other tools.
There's other AI tools that can split the audio into stems, though it's not a perfect solution since it introduces artifacts. Good enough to lightly remix and adjust levels, but taking whole instruments or vocals out usually leaves the mix sounding fairly hollow.
