fish is a fine baseline but I want better shell scripting (murex, xonsh) and manipulation abilities (nushell). For the software world, shells are evolving unusually slowly.
Do they need to change much? I strongly think that they do not.
Now, with fzf in combination with other tools, I often ask myself: Why isn't this the default in most shells? When I now use bash, it seems very archaic.
Yes, there are a lot of improvements one can do with shells. I should start making a wishlist.