Good point. Since those currencies rarely go above 1.35 it would be a wash at best.
Yes if you have your own travel category purchased being done on the card (or are okay redeeming for gift cards).
If you don't have any travel categories being booked on the card (to redeem the points for) and need to sell the points as travel at a discount (say to a broker / travel agent), the math changes.
If you sell at 10% discount ($2k booking for $1.8k), the transfer ratio equivalent would be 1.2, so you come out ahead getting the Amex/Citi rates (1.3+).