tcsh was the default shell before that, and it didn't help much with its popularity, and for interactive usage tcsh can do most of the things bash can and is mostly okay (not scripting though).

I think being the de-facto default on Linux as part of "GNU plus Linux" has more to do with it.

Make sure you check out abbreviations

Like aliases but they expand in-place, so auto completion friendly, easily modifiable, etc. Love them

$ abbr s sudo

$ s<space> -> sudo