In some industries, unions fill this nieche.
Come to think of it, this might be a good way for software unions to get a hold in the US. The Union will have a process to validate the competency if its members, and validate their careers, meanwhile hiring managers who are looking for guaranteed engineering quality will be able to find them, and unemployed engineers will be able to find work quickly, only bye the may benefit from the power of collective bargaining.
Kinda like a recruiting agency, but without for-profit motives and the shareholders will be the union members.
I don't see any downsides, except dkr the usual "corrupt men on top" problem which plagues any hunan organization, though mandating that leaders have extencive industry experience could slightly mitigate that.