If I'm honest I don't often iron bedding, but I recognise it would look much better if I did.
However, when I do spend ages ironing duvet covers, sheets and pillowcases, they still don't really look "good". And the one set of high thread count pure cotton bedding I have always looks awful, no matter how long I spend ironing it, it's impossible to get the creases out.
Tumble drying, which I always understood reduces creases, seems to make matters worse.
What am I doing wrong?