As I mention in my discussion of Deanna’s Insurrection outfit, the crew’s undercover hero wear is generally basic.
Jean-Luc wears what amounts to a t-shirt, leather jacket and jeans.
There are vague nods to it being a t-shirt, leather jacket and jeans from the future in the tailoring (and lack of labels). Mainly, the collars of both the jacket and shirt are unlike anything we can buy off the rack in the present.
This outfit is earth toned, and fits the ‘scholar who will punch you’ aesthetic Picard prefers.
While Picard is not dressed in his signature wrap shirt date wear, his love interest, Anji, is.
This costume is bland, but it is meant to be, so he blends into the crowd. Unfortunately, I personally find the relationship with Anji, and the film entire, just as bland.