The flaw of course is that $200 is not opportunity cost. Your time is only worth money if you’d otherwise be working. So when I get home from my 9-5 job where I make a fixed salary, and fix my faucet, that job just got done for free. There was no opportunity cost because I don’t get paid hourly and was already done with work for the day.
I’m a rather extreme DIYer, and I can confidently say I would not live the lifestyle I do if I paid people to repair my car, build my furniture, cook my food, mow my lawn, do all my home improvements, plumbing, electrical work, fix my electronics. All that labor adds up, especially in the expensive Bay Area. If you take what you’d otherwise spend on all that, starting say age 20, and instead put it into your retirement account you could probably retire 5-10 years early.
You have to do the math on this carefully though.
A lot of people think like this. I get paid $200 an hour, my electrician gets paid $100 an hour, therefore I should pay my electrician $100 and use the time I saved to make $200. But plenty of those jobs don't actually take an hour, even though that's the minimum billing time. So when they take ten minutes, you've got to pay the electrician $600 before you save enough time to make $200 yourself.
Then you've got a transaction costs problem. You called the plumber, but now you've got to let them in, explain the problem, review the invoice, submit payment. It could take the same amount of time as doing it yourself. It could take longer.
Then you've got a knowledge problem. If you take the time to understand how things work then you see warning signs, so you fix things while they're still a $5 problem instead of not understanding that it will turn into a $5000 problem. Or in reverse, not realizing that the person you're paying for services is charging you $5000 for something that could still be fixed for $5.
Then you've got a tax problem. You thought you were "making" $200, but actually half of that is going to taxes, whereas 100% of the money you're spending is actually getting spent.
The result is that the person who works more and pays for everything instead of doing it themselves has a higher annual income on paper, but less actual disposable income because they lose more than that to taxes and costs, and less free time because they're actually working more in reality.