I think high end hotels are a waste of money if you just sleep there. But if you fully utilize its amenities and facilities, it is totally worth it. Four Seasons on a weekend business trip? Count me in. But if I am going somewhere for the first time and have a jam-packed sightseeing schedule then splurging on a hotel makes no sense.
With all that said I do believe Aman hotels are disappointments to say the least. For thousands of dollars a night you get not much more than something like the Four Seasons, MO, IC, etc. Especially in Asia when service is great at any hotel.