A vote is done because no one person or even small group of people should be able to decide something that momentous. Votes are not rational. They are typically the result of a human herding instinct.
That said, it is a decision that most people will live with (well, perhaps excepting you). They realize that a clear, if slim, plurality desires this. The WHY is mostly unknowable. As long as everyone agrees the vote was fair, criticizing the result after the fact makes YOU look bad.
You want to have a positive effect? Move on from this. As you pointed out there are a myriad of details on how this is to be done. Try and salvage the good aspects and deal with the result.
The People Have Spoken. Stop whining. It won’t get you anywhere.