Sorry but that's nonsense.... it never was true, and even less in the last couple of years. It might be true that service can sometimes be lacking a bit, don't expect service like you get in Asia, but that's not any different from most western countries. Amsterdam hotels are rather expensive and that's why people might assume they are in the same league as some of the truly luxurious hotels you might find elsewhere...

What people should start with is not just looking at the US based chain hotels, even though the Andaz and the Waldorf are pretty nice. But there are more independent options that are good too like the Conservatorium and the Dylan.
Personally I don't like the Pulitzer due to most of the disappointing rooms, but some do.