[allover]

> Or am i missing the point completely

Sort of. These are ways you can built web components today with modern conveniences that some of these _libraries_ (not frameworks), might lend you.

The site isn't claiming these different approaches can all be used together on one page in a practical way.

Technically you could, but it would have the obvious downsides you mention. This is just the reality of the limitations in the standards today.