Taking the medium- to long-term view, this makes sense. Hanley is not the future. You can play around with lineup configurations and roster moves to maybe find something that makes more sense short-term IF Hanley hits like he has been capable of. Between his age, the option vesting, his pattern of decline, and his defensive liabilities, I don't see that his positives merit keeping him around. This is the time to cut bait. No point in vesting the option if he's not in the long-term plan.
Kind of sucks because I like the guy, and he is capable of mashing still when he's hitting well.