Meat isn't a political thing, despite how they may portray it as such. In 1950 people were still recovering from the effects of the wars, diet wasn't as much of a priority.
The quality of food in general has greatly decreased my very the decades, I would say it is at an all time low because of the mass involvement of corporations more interested in profit rather than quality.
I ate predominantly plant based for years. All I can say is you have to try it for yourself, and perhaps listen to some people have discussions and debates on the topic.