Thanks for the inquiry. Your first question is a pressing one, and it feels like we are declining, especially in America. But, actually China’s Christian growth is dramatic. Also, I went to Wikipedia and wanted to edify you with the stats there:
According to a 2011 [Pew Research Center] survey, there were 2.19 billion around the world in 2010, more than three times as many as the 600 million recorded in 1910. However, this rate of growth is slower than the overall population growth over the same time period. According to a 2015 study, by 2050, the Christian population is expected to be 3.0 billion.
According to the [World Christian Encyclopedia] approximately 2.7 million convert to Christianity annually from another religion; World Christian Encyclopedia also stated that “Christianity ranks in first place in net gains through religious conversion.” While, according to “The Oxford Handbook of Religious Conversion”, approximately 15.5 million convert to Christianity annually from another religion, approximately 11.7 million leave Christianity annually, and most of them become irreligious, resulting in a net gain of 3.8 million. Christianity adds about 65.1 million people annually due to factors such as birth rate and religious conversion, while losing 27.4 million people annually due to factors such as death rate and religious apostasy. Most of the net growth in the numbers of Christians is in Africa, Latin America and Asia.
So, we are blessed by millions of Christians influencing the world through the Holy Spirit with love, charity, care, understanding, and general brotherhood/sisterhood. In the United States culture, we are seeing a decline. That is why hopefully we can come together and encourage peace through Christ to those around us. This site helps, so it is a blessing to have you here to chat and fellowship with.
As to the 2nd question, I think the God has spoken in some fashion with every person through different methods. But your question is a good one. In order for the story of redemption to be told God would have had to spoken to “someone” first. It was the Jews. But, did God spoke to others, I would say no question about it. Adam was created. God talked with him. And, Eve too. Additionally, just thinking off the top of my head – Belshazzar (Babalonian) in Daniel 5 was given writing on the wall from God. And, all the way from antiquity through the present, God has come to this world not only in person through Jesus (God) who spoke to so many non-jewish people but also to so many through visions and dreams. I hope these thoughts perhaps give minor inroads to some of the really good questions you have. God bless.