I'm sure there are some pipefitters who make a lot of money, but we should go by averages, not outliers.
The average for "Plumbers, Pipefitters, and Steamfitters" is $56,330 per year, according to the BLS. For "Software Developers, Quality Assurance Analysts, and Testers" it's $110,140 per year. For "Physicians and Surgeons," it's $208,000 per year.
We also need to consider that running your own business is a lot of work, and doing physical labor can be hard on the body. One of the benefits of office jobs is that you get high pay, stable hours, relatively low stress and get to work in an air-conditioned room. So I would still prefer that over skilled trades even if the pay was the same.
The average for "Plumbers, Pipefitters, and Steamfitters" is $56,330 per year, according to the BLS. For "Software Developers, Quality Assurance Analysts, and Testers" it's $110,140 per year. For "Physicians and Surgeons," it's $208,000 per year.
We also need to consider that running your own business is a lot of work, and doing physical labor can be hard on the body. One of the benefits of office jobs is that you get high pay, stable hours, relatively low stress and get to work in an air-conditioned room. So I would still prefer that over skilled trades even if the pay was the same.