For flat beds like the one in the picture they should be up high.

My cat has one on top of a bookcase in my office that is her go to spot (seriously the nice cat tree I got her is only used for scratching and as a platform to get to the bed).

Enclosed beds usually work better on the ground as it allows them to feel safe.

Ours just sleep on sofa and beds

Try putting it in an elevated position. Most cats will like and use it more, even if it’s only 2 or 3 feet off the ground.

Same. Our cats prefer cardboard boxes cut down to be about 3” walls vs a commercial cat bed.