The person willing to name a tradeoff has made the choice easier to assess honestly.

Most proposals arrive with the costs left out, which makes them sound better and makes them impossible to judge. Someone who says plainly what will be lost gives everyone something real to weigh, and they usually pay for that honesty in enthusiasm. Hidden costs do not disappear, they turn up later attached to a person who never agreed to them. Naming a tradeoff early is what makes agreement mean anything.

When you next put something forward, say what it will cost and who carries it. And when a plan reaches you with no downside mentioned, asking for one is reasonable rather than hostile.