Maybe you're special. And contracts can even be negotiated with a group to recognize individual performance! But the data is pretty clear that when workers bargain collectively, they can negotiate higher pay and better benefits.
At least people can actually measure seniority.
For example, a ballplayer can't waive a CBA_specified contrast constraint (e.g. many performance incentives are disallowed, can't work for less than the CBA-mandated minimum, etc.).
they can choose to not include certain things