Something we also take for granted in the tech world is companies running on ridiculously high net margins. Apple, for instance, makes about $400,000 in
profit per employee. They could literally give every single one of their 123,000 workers a $200k raise and still be making tens of billions of dollars in
profit per year. Now let's consider WalMart, the largest employer in the US and one many have chastised for poor pay. The make a bit less than $4,300 in profit per employee. And that's one of the largest companies in the world that can take advantage of economy of scale to push their profit margins as high as possible.
Most companies operate on very thin margins, made up for by scale. Selling $300 hardware for $1000 is, fortunately, an exception rather than the rule. But what this means is that unions are not going to suddenly send major benefits towards employees, because the companies simply do not have the money for these benefits. Factor in the frequently unreasonably high union fees and unions are often going to be a negative overall outcome at many companies. For instance the united autoworkers union demands 30 hours of pay, or 1.44% (which is 30/2080) of your annual pay in dues per year. So in other words workers would need to see an extra 30 hours of pay or a ~1.5% raise, just to break even.
But many people don't consider economic realities when they believe they can get more stuff. If you had a national vote on enacting a $50/hour minimum wage you'd have tens of millions people vote for it even though it would lead not only to their direct unemployment, but also throwing the entire nation into complete chaos and crashing the US and world economies as well. For instance you regularly see things like employees trying to unionize at companies that are operating in the red. What exactly do they think is going to be the outcome there?