Fundamental in what sense? In most of the world, most of the industries are not unionized. And where there are unions, they came after the line of work started. Which makes unions seem not fundamental at all.
> In Europe there isnt a single job without an union behind
Not true at all. Most professional service oriented jobs are not unionized. Even in places like Germany where unions are relatively common.
which means growth of unions is just a matter of individual choice of each employee. and there is nothing the company can to to stop it.
Not correct for the whole Europe.
In some places in Central Europe you do not have a Union but instead Work Council that intermediates and oversees the management and acts in the interest of employees.
Personally I like the idea, but at least in some counties it became an instrument of job protection for old employees that sometimes has a different agenda than other employees.
They are fundamental in that they blunt the threat I face if I fell out of my present line of work and had to take something that would rough up my baby soft laptop jockey hands. If they have a better bargaining position, I have a better bargaining position because it's less of a loss if I have to join their ranks.