Why SO MANY Foreigners Living in Thailand CANNOT Speak Thai?

Recently on my birthday a monk asked me why I don't speak much Thai. I could hear what people say about me. 

I answered because I don't want to hear that. 

I do have a bit of a memory problem. Can't remember people's names unless I am in contact with them on a daily basis. Even then it can take months. 

Most of my Thai friends have learned enough english and sign language to communicate with me.  Of course there's always online translate

Twenty years ago Thai media was publicizing the government's intent to have more english proficient Thais. That ended when Chinese tourism peaked.