Going further than an IT workers union with the CNT

I find their "current status of the industry" interesting:

Today the industry is highly polarized as far as salaries are concerned, having one end with fairly high salaries compared to the rest of the working class and the others with wages just at or even under those of the collective agreement applied, since they don't have their own agreement.

The vast majority of companies in the sector today are temporary work agencies in disguise and their profits come mostly from the illegal assignment of workers. The most common contracts are for specific work and services and the easiest way to improve working conditions or salaries is to change company. Because of this, unions have little presence and workers have little interest in unions. After all, why fight to improve conditions in a company which you will leave in 6 months? The lack of a union presence allows the employer act with impunity and causes workers to be totally unaware of their rights. Which encourages things like mandatory but unpaid overtime, endless workdays, the lack of a proper collective agreement, general helplessness, etc.

I wonder how true this is. Are IT workplaces really just like temp agencies? I don't think they are, but the contracting and subcontracting through freelancing can be hella irregular, kinda like a temp agency.