I'm not trying to be an anus, but temp stands for temporary which is not long term. It looks like they are looking to improve individual skills that are in demand in order to progress to a full-time job. Once they have relevant actual experience with companies it will be much easier to find a long term employment situation.
But in the recent past, the most recent decade especially, companies have infamously been using temp jobs as a means to get around paying full-time salaries and benefits perpetually. Same with internships. For lower level white-collar workers, the progression isn't from temp job to permanent job but temp job to temp job to temp job to early underfunded retirement.
Not that I see an easy way out of this--companies of all sorts are driven to this behavior inexorably by the market--but people genuinely interested in transitioning to a better economy for everyone have to look at this fact head on.
My statement is purely descriptive, which I note you don't controvert. White collar temp jobs have substantially increased their share of the economy relative to the mid-20th century. And the structure over time of career progression is also substantially changed as a result of that.
Saying, "well, they chose to do it" sidesteps analyzing the systemic issues. No more than saying "well, black people choose to work for less pay than white people" analyzes anything meaningful.