well, yes, it did work. the side effects are horrible, and often the disease was better than the cure, but it worked, similar to how being dead also is extremely effective for managing depression.
Murder is a very successful cure to a lot of ailments.
I feel like you're not getting the very obvious implied point in that no one thinks lobotomy was good practice in retrospect
The guy I replied to seemed to, after I mentioned lobotomies as an example of physical treatments for "feeling sad" that are now seen as barbaric.
https://en.wikipedia.org/wiki/Lobotomy