I tried really hard to get into Nushell but gave up after a month or two. Muscle memory with backgrounding was my big issue -- I tend to edit in helix and then background for a while and then foreground, and I seem to recall this totally freezing or crashing nushell somehow. Tried to learn some kind of recommended alternate workflow with pqueue (? I think) but just couldn't get there.
Yeah prior to background job support, pausing the foreground process with CTRL-Z was a major footgun—nushell didn't detect when the foreground process was paused, nor did it offer any way to unpause it. The terminal was rendered useless until you manually resumed/killed the paused process via another terminal or GUI.