I gave up worrying about this nonsense over 30 years ago. Firstly the WBC at that time introduced something called an international title. Which was similar to the interim titles these days confusing the public.
Then the British Promoters decided to give credence to the WBO, and younger fans might not know this but the WBO was as lightly regarded as the IBO is today. Neither the fans or the Boxing Press gave much recognition to it.
In Britain even with the 3 other belts British fighters hardly ever won world titles. So the Promoters here went with the WBO and suddenly at the dawn of the 1990's we had World Champs left right and centre.
A few years down the line even the WBO became too hard for British fighters. So Promoters here recognised the WBU title. This WBU was Started by some guy at his kitchen table. I think Ricky Hatton is the greatest ever WBU champ. That organisation split into to two groups and has more or less disappeared.
And we also had the WBF title. It is still going and Johnny Nelson for a brief period in history was the WBF heavyweight Champion of the World.
With out the WBO title, guys like Chris Eubank and Nigel Benn would never have become British legends. And Ironically the best British Middleweight of that generation who was avoided by both of them that is Herol Graham. Has by and large been forgotten. Only remembered the Boxing Nerds from that era.