Is there any performance difference between bundling JS in a plugin, vs the same JS in a standalone JS file? (like CustomJS)

How much of a performance / speed overhead is there in loading a plugin itself, however much JS it has? Obsidian has to load plugins before opening your vault, would it help performance if I offloaded JS that doesn’t need to be in plugins (like mouse or keyboard events, or other types of events), into scripts that can be invoked with commands, like with CustomJS?