Speaking from years of experience in IT (nearly thirty of them), I can give my own unscientific opinion: because people put too much faith in certifications, and refuse to do any on-the-job training. You can have five of the six skills listed in a job ad, but if you don't have that all-important sixth one, your application will get round-filed. It doesn't matter if it would be a simple matter to train a tech on that one thing. Businesses want phoenixes for chicken scratch.
Certifications are a boondoggle, and have been for years. The tests have been rigged in such a way that candidates need to take them again and again to pass, and they get charged a fee for each attempt. The test itself is a revenue source for companies. The "prestige" those certifications bring for the companies that front them is based on their difficulty, not on their relevance or fairness.
I once attended a Microsoft certification "boot camp." We all worked our asses off, studied the material, and most of us passed at least one test. Nobody passed all three exams except for one person. I had noticed that person using test prep software with a logo that didn't match the stuff we'd been given. It looked like an orange DNA helix.
After the last test, a bunch of us milled around outside the building, and I asked the guy who passed how he made it through. He ran for his truck so fast that there was practically a dust cloud behind him. That's when I decided to look up that logo on Google.
He'd been using a "brain dump" service. For those unaware of what a "brain dump" is, it's when a third-party company sends a bunch of people to intentionally fail the exams over and over. During each attempt, those people memorize the test questions. Then the company has their plants aggregate all the possible questions in an exam pool and the correct answers to them. In effect, it's a copy of the whole test.
Brain dumps are extremely common in IT. When I worked at VMware, many of our own employees used them to pass certification exams that were mandatory for continued employment. Those people had been doing their jobs for years. They just needed a bogus piece of virtual paper to prove it to our executive leadership. It was all about appearances.
Why is tech struggling for qualified workers?
Because it refuses to acknowledge them.
My partner's employer recently tried this. He works for a mental health agency. That mental health agency has issues with compensation, recruiting, and retention. Yet the CEO insisted that everyone come back, despite the fact that productivity has improved with remote work. In fact, a lot of their patients prefer telehealth.
"Take a title demotion, come back into the office, or quit. Pick one."
The mass exodus has been astounding. There's no chance they'll be able to fill in the gaps left by senior clinicians. Demand for psychologists is sky high right now, and just about every other employer pays more and allows telework.
The patients will be the real victims of this attempt at a "power play."