If someone is hired on your team that's allegedly under-qualified (at the time of hire) and isn't able to earn their stripes at work (despite being given the opportunity to do so over a long enough time horizon) then they have no business complaining that they're not getting work that delights them. This argument applies to literally anybody regardless of their sex/race/age/orientation.

GP is basically advocating the collection and use of data to verify and possibly correct any manifestation of this alleged unconscious bias. Just because the data isn't perfect doesn't mean it's useless. You seem to be OK with pre-meditated "correction" without looking at the data. You even seem to think that the collected data would vindicate managers of allocating "less glamorous work" to the non-high performers.