Except that studies show that users expect both similar content and experiences regardless of device. Responsive web design, with progressive enhancement, is the foundational bridge to make this experience work well.
Just because someone experiences a less than ideal experience of RWD in one or more places doesn't mean to group all RWD UI experiences together as bad.
It's more practical spend less time developing and testing one global component than more than one.
I think there's a "theory" of rotating UX (same features in one way when in one space, another way in another space). But I can't find writings on this.
Browser spec creators and browser vendors have been implementing touch and non-touch UI differences in common primitive features since the 2010s. Example, if you use at a <select> element on desktop browsers and mobile browsers, I would say it falls into a similar idea as rotating UX. There are countless other examples, too.
Could there be improvements? Absolutely, and that's where we get to have a voice.
Just because someone experiences a less than ideal experience of RWD in one or more places doesn't mean to group all RWD UI experiences together as bad.
It's more practical spend less time developing and testing one global component than more than one.