Buff, Wheeler, Little will continue to get a year older no matter what. Trouba situation will remain the same no matter what. None of these things are impacted by trading for Stone as a rental.
On the other hand, imagine if the Jets trade 1st + KV for Stone then get knocked out in 2nd or 3rd round and fail to win the cup – Stone moves on to another team as UFA, Buff, Little, Wheeler still continue to get older, we still have to move Trouba for futures, we now have no KV to slot into the lineup or be trade bait for a player that can help us in the medium-long term, we have no 1st round pick to draft a cost efficient player or to serve as trade bait for a player that can help us now.
That scenario is far more terrifying and harder to dig your way out of then if Chevy were just to stand pat, miss out on the cup but still have his top assets.