Maybe not, Picard could have seen her as a kindred spirit, one assimilated so young and unable to even try to resist assimilation like he had tried. Also if the events in Unity
happened to Riker as they had to Chakotay, Riker could have been her advocate and fought to keep her aboard especially once her link was severed.
Picard would have seen Species 8472 as the threat they were at the time, and like Churchill and Roosevelt with Stalin, Picard would have seen the Borg as the lesser of 2 evils and joined forces with them.
Picard may have made Seven do a lot more to prove her willingness or at least her resignation to joining the crew and not betray them.