Cherry-picked example. Although I do think the Conservative opinion of skilled trades is not really rooted in reality. Most of the better-off tradesmen are sole proprietors.
And of course, the trades aren't a panacea. Demand ebbs and flows and sometimes work can be hard to come by. But I see nothing wrong with suggesting it as an option to a college degree (and the debt that goes along with it). Even if the salary isn't that high, it still beats being unemployed with $20K in student debt.
That's like saying the better off developers are senior software architects or consultants.
If you want to optimize your trade career for money owning your own business is simply where that path leads.