I lied about my potential value (by understating it) to an employer for (longer term) personal and professional gain.

Going back to Union Salting:

Often times the "salt" is a star employee; they're always on time, never say no to a job, pick up shifts nobody wants to take to ingratiate themselves both to management and their colleagues. They don't ask for raises and never complain to management. Their intention is to organize workers and so they want to be the sort of model employee a manager will keep around.

The reason why this practice is allowed is because its illegal for unions to walk into an establishment and talk directly with employees about organizing while they're "on the clock" and on premise.

The parent didn't think they were irrelevant at all, they thought it might signal to the company that it could extract more value by assigning them work they didn't want to do.