A framework component is effectively a reusable block of code. It's an organizational principle more than anything; modular and reusable, but not meaningful to the browser in its own right once rendered. A web component, on the other hand, is very literally a new HTML element, and is treated by the browser as such. Once defined, the browser itself sees that component as a meaningful entity in its own right.
While the difference between those two ideas is fairly subtle on the surface, there's a whole nest of smaller differences that result from it. For just one example, web components are perfectly AJAX-compatible with no extra strings attached - you simply add the HTML tag representing a component to the DOM, and it works out of the box, no matter when or from where you got it. Achieving that with a framework component requires some additional work at best, which may or may not have been done for you by the framework authors.
That's not to say one is necessarily better than the other either, to be clear - they're just different, and treating them as if they were the same does both a disservice.