For me the biggest issue is not having history. That’s the value of the terminal - I can scroll up and see previous interactions, copy paste from them, etc.

That said I don’t think the point of this is to replace sed, or other unix-y tools where you’re having pipeline-oriented programs. It’s full blown apps inside of the terminal that might otherwise be in the browser or in a GUI. Something where you’re seeing things update or otherwise interacting such that you could never grab it’s out for a shell script nor would want to.. like running a REPL or top.