reminds me of those flowered bathing caps from the 60s/70s

I agree, but that's not the worst thing about them -- THAT is actualy kind of fun. To me, one of the worst things that anything can have going for it is for me to immediately be able to imagine how quickly it will start looking truly terrible.

That said, if I saw these in person, and if there were way that these were made of some material that made me feel that they would break the laws of physics and stay pretty even after being smooshed, I might end up saying that I loved it, because it's not actually ugly, per se.

I really like these... esp the red one!

All I can imagine is someone trying to lean against it on the sofa, and constantly shifting, like there's something wedged between them and the pillow...

not a fan of these, but wouldn't they be used to decorate a bed, rather than a couch?

Wherever they're used, they negating their primary function, which is to provide cushioning and comfiness.