You can build consensus around the decision making process and build a culture where the outcome of that process is widely accepted. As long as people have the time and pathways to make their case and input, and understand there will be some verdict that may or may not align completely with their opinion. Then its just the decision makers duty to synthesize things in good faith but probably has bought themselves some leeway.
One thing I like to do with sr+ engineers who will feel burned by a decision - esp. those very publicly against it - is to lead with some sort of concession... maybe a project they expressed interest in, greenlight for a week to research some POC.
Whatever it is, it tends to be considerably less value to the business than the decision itself, but it directly acknowledges their discontent and allows them to get something out of the process besides platitudes, (perceived) public embarrassment, and frustration.
