Using multiple Linux or Mac Shells side-by-side opens up endless possibilities in terms of the tools the user wants to use for any sort of filesystem operation. Things like sed, find, xargs, grep, cat and many more come to mind which allow for maximum flexibility for any sort of task. See here https://www.gnu.org/software/bash/manual/bash.html
In case you have doubts about missing functionality existing in the original tool TotalCommander please give me an example and I'll (try) show you the bash aquivalent.
Ranked in these QuestionsQuestion Ranking
Pro Maximum flexibility
Pro Open source
Not only is bash constantly improved by the community but it also is free of charge.
Pro Command-line interface (cli)
Clean, to the point and clutter-free.
Pro Vast amounts of built-in commands
Usually pressing TAB allows to auto-complete commands and paths. With packages such as bash-completion auto-completion can be even further expanded.