The other aspect I think people are missing is that, for the right person, the choice isn't between a white collar office job and trades, it's between struggling in retail and service work with a (possibly bad) degree and no upward mobility, where your only escape is into either management or retraining.

For those people, trades are absolutely a better choice - it's not like becoming an HVAC dogs body prevents you from later going to school if you decide it's not for you.

Yep, conflating retail/hospo dead-end jobs where you get trained up in a week and replaced in a week with qualified tradesmen doesn't like high quality research.