What is the main advantage of fast lookup in a constant value tree?

The main advantage of fast lookup in a tree of constant values (for example, in Python's match/case construct) is that the search is performed in near-constant time, thanks to the use of a data structure optimized for quick matching with fixed values.

Instead of sequentially checking all options, a constant value tree allows you to immediately jump to the required node based on the value, significantly speeding up the processing of a large number of options.

Example: if you have a set of fixed keys for matching, a constant value tree allows you to quickly determine the corresponding case without checking each one in turn.