For some people who have big businesses, they can indeed become rich without investing, but what needs to be considered is that only some people are like that and many people also achieve wealth by setting aside some of their income and starting to invest, it will have a big impact in the future.
The purpose of investment for people who are already rich is to increase wealth as you said, but the rest of the people don't think that way, in fact many people start investing to achieve wealth in the future, so I think people need to invest if they want to be rich.
Yes, it is true that by investing people can become rich, but of course only those who believe in investment and feel it themselves. Because it has been proven, unlike those who have not felt the benefits of investment, of course it takes longer to learn about it and understand it, but it is true that people's opinions always differ depending on what they feel. And the longer you invest, the greater the growth in profits you will get and that's an interesting thing.