If you signed up to a seniority based airline knowing that you'll be shafted until you work your way up the ladder, you have no right to complain that an airline is enforcing the principles that you agreed to when you joined. The fairest outcome is the MOA being adhered to, to the letter. Otherwise you're essentially agreeing to having your agreements torn up to suit the company whenever they see fit, especially if it's proven to divide the workforce.
Whether or not some of those at the top of the tree should be considering if they really need to bankroll their grandchildren through private school or if buying that second boat in the coming years is absolutely necessary is another matter. I'm sure there's plenty at the top of the seniority list in BA who wouldn't be missed by the company or those who sit to the right hand side of them.