I think with hotels or planes etc, it is entirely reasonable to say that one should expect to stay or travel in the category booked. Any upgrade is a bonus.

It is well documented here that NUA or status upgrade availability is not equal to cash availability. Usually it lower. But sometimes not.

On Saturday I stayed one night somewhere where I had booked the base room on points a week earlier. There were no higher category rooms available for cash all week, but 2 days before check-in my reservation was upgraded to a suite. Lucky me.

But upgrades through any means have never been guaranteed. Especially nor have NUAs. Thinking a holiday has been spoilt because one didn't get what wasn't guaranteed or available and one didn't pay does come across a bit churlish. Sorry.