Marriott selling gift cards at 20% off is a far superior way for a hotel chain to raise cash in hard times, than Hyatt selling points at 23% off, hence OP's very valid question here "that's it?".
Not to mention that Marriott's sale is counted as "travel" so people can get 3x on Chase UR credit card or can get 6x on Marriott branded credit cards, unlike Hyatt's sale where you get 1x.
Hyatt could come up with a gift card sale as well in the near future, but the problem will be that there is a first mover advantage here. People who loaded up on Marriott gift cards will not have as much budget to spend on Hyatt gift cards. Speaking of people who like to stay at both chains of course...