You’re paying with your body, the work can be very dangerous, and it takes a while to ramp up to decent pay. On top of that the pay isn’t always going to be better than a degree (iirc research has concluded that lifetime earnings for trades are behind degrees), ignoring countries with sensible tertiary education options.

Trades are not equivalent. And education is still a significant indicator of political alignment.

Honestly, this is a great example of the empathy gap.