My father and brother are in the construction industry and we were talking about this awhile back. I've spent my entire career in the green industry and the labor woes are very similar so we all were able to commiserate.
My dad's main complaint was that people just don't want to do the work anymore, regardless of pay. He starts his general laborers off at $15 an hour, which isn't too bad for people with a high school diploma or less. His skilled guys do much better than that and he can't find anyone to fill the jobs and it seems to be getting that way across the board in these manual labor trades.
The points listed in the article are pretty much spot on, but I think the bigger issue is that the blue collar worker is disappearing quickly and it's not just in the construction industry. I think you're right that technology and the push for everyone to go to college has had a big impact on this, and as such young people don't have the same skill sets that they did 20 or 30 years ago. If working with power tools, or manual labor is a foreign concept to a young person, then they most likely aren't going to gravitate towards a trade or blue collar industry. And this sounds awful to say but when you don't have people that view these types of jobs as a career you're often left with less than motivated and unambitious workers to choose from.