Comment by neandrake

Worktrees are useful particularly because they look like entirely separate projects to your IDEs or other project tooling. They are more useful on larger projects with lots of daily commits. If you just use branches then whenever you switch, in the worst case, your IDE has to blow away caches and reconstruct the project layout or build the project fresh. On large projects this takes significant time. But switching your IDE to a different project, there are now two project and build caches to switch between.