Luxury is hard to define, as for me it encompasses luxurious facilities/grounds and luxurious service...
Off the top of my head here are 20 hotels from most luxurious to lesser so (though still arguably luxurious) that are/were bookable with points:
W MLE
PH SYD
PH MEL
PH EZE
PH CDG
PH ZRH
The Plaza NYC (Fairmont)
GH LIH
SR Princeville
SR Bal Harbour
Fairmont Kea Lani OGG
Fairmont Pacific Rim YVR
Fairmont Copley Plaza BOS
W HKG
SLS Beverly Hills
Andaz 5th Ave
Westin Moana Surfrider HNL
Westin Europa VCE
Herrod's Vitalis Spa Eilat
Mamilla Jlem
Not going to insult the other hotels by including the PH Aviara, PH YYZ, HR Huntington Beach, HR OGG, HR AUA etc.