Agreed. In that sense BA did it so more sudden. And as discussed before, before the change to XP your status miles or segments above a threshold for Gold or Plat also were forfeited. You had to gain miles and segments all over again, without rollovers. And usually there is enough incentive to stay loyal to your main FF program - the perks FB gives with free (comfort) seats, bags, lounges and fast lane are enough for me to stick with them after you reach a threshold unless competition is really way cheaper (that is, flying Y or unbundled J). Not to mention that some partner flights may give you really a good bunch of miles that do not expire and that you can use later.