This always ends up being exaggerated though, by some who want to diminish the importance of higher education.
There's high demand now because of good times. A lot of those jobs tend to be highly affected by economic downturns, and overall that diminishes the value there, as even if you make good money in good times, you may have to balance that against a higher chance of unemployment vs someone with a higher education degree.
Yes, economic conditions could definitely come into play but the average age of Tradesman is really high and they are retiring at a rapid rate. It's not a matter of devaluing education, it's a matter of people getting past the cliche that everyone needs to achieve a bachelors degree to be successful.