it runs great, no problems on the performance front. the controls do not lend themselves very well to gameplay on the steam deck though. there's some good community-made control layouts that kind of help, but due to the interface being catered towards having a mouse available, be prepared for a slow and tedious time.
If that doesn't sound like a deterrent to you, then by all means full steam ahead! be aware that Dwarf Fortress doesn't have cloud save functionality, so if you were wanting to play the same fort on both PC and steam deck, it's unfortunately not possible.