Ever heard of addition by subtraction? I genuinely feel the Blue Jays are a better Baseball team if Santander is not playing the OF. Your point about Lukes and Davis not being able to duplicate their successes from this past Season are valid. But both are projected to out perform Santander this coming Season. And that's without a platoon or ideal matchups. It's something to consider if given the opportunity.
Santander is projected for like 1 WAR by Steamer right now. That's really a bat we want to squeeze in the lineup to make our OF defense worse? Was one of the strengths of the team last year.