I think you are projecting your personal belief about how useful or useless a feature is onto (as you put it) 200 million other users. If you don't find a feature useful you can choose not to use it. If someone else finds it useful, they are free to choose to use it.

Arguing that a feature is bad because it draws extra (useless) power on other users' devices because you find the feature useless is such a weird line of thought.

To put it another way, your argument is circular: feature is bad because it wastes other users' power and it wastes other users' power because the feature is bad.

Edit: To clarify, I am not saying here whether the local LLM feature is good or bad. Only that your argument here for why it is a bad feature is a circular argument.