If you need a tree, it's most likely that you want some custom operations on that tree (e.g. parsing text into the tree, pretty-printing the tree, traversing the tree in various ways, etc.)
At some point, the tree is just a data structure and what you're interested in are full-blown, non-trivial algorithms/programs for fairly domain-specific tasks. In these cases, a library (or even custom implementation) for a general purpose programming language is more useful than a tool (a la Excel or vim).
Viewed in this light, it's not unsurprising that we have many domain-specific tools for manipulating trees. Most of the proof assistants have a GUI based on Gentzen-style sequents.
LaTeX has styles for type setting proofs which look like the ASCII ones in the article.
Tools for generating parsers often have tree-based UI's.
And so on.