How to use 'people' and 'they' [duplicate]
Solution 1:
I would add that 'they' is more specific than 'people'. In the first sentence, all the people within a certain definition, class, or area heard the news but the bravest volunteers among them came forward. In the second sentence, 'they' refers directly to 'the bravest volunteers' who came forward because they heard the news. Whether other people also heard the news or not (in sentence 2) is somewhat irrelevant.