First I told him about survivorship bias and laid out basically the same statistics as in the article. Then I showed him that he could double his income in 3-5 years just by learning the craft of software engineering - risk free -- and still have plenty of time to enjoy his new marriage and enjoy his hobbies.
If his own company was struggling, he would be up late worrying about it. If the company he is working for is struggling and he keeps his skills up, he could easily get another job in our metro area. It's been that way for me for over 20 years.
I enjoy being a corporate drone, I go to work every day and leave the job at work -- and I'm a technical lead -- imagine how easy it is if you are "just" a senior developer? If you are a two income family in a good job market with one income as the average senior software engineer, you are guaranteed to be well within the top 10% of earners and be able to live a pretty good life.