The thread title says it all, really. I am tall and don't really like wandering about in what look like cropped trousers. I also don't much like cuffed ankles, though could live with them if they were at least not half way up my calves.
But the main thing is that I tend to sleep on my front and find buttons uncomfortable.
Jasper Conran at Debenhams did some lovely wide-leg PJs with a T shirt type top a few years ago. I bought several pairs but I've nearly worn them out and lost weight so they're in danger of falling down if I wear them round the house.