But people born now are without that excuse.
A way of answering your question might be to answer the following: “How were people saved prior to Christ’s crucifixion and resurrection?” People then were saved by responding positively to God’s revelation. In other words, people are held accountable for what they know. How much light has a person received from God? Whatever that is, that is what they’re accountable for. The same would be true for people today who have never heard of Yashua.
If someone lived in China prior to Christ’s death and resurrection, how could they be expected to believe in Yashua's death and resurrection for the forgiveness of their sins? Obviously, they could not believe in something they had never heard.