I think OP is onto a good analogy but it feels somewhat strangely mapped. To me, life should be JavaScript. (And conversely, JavaScript is life?). Most things don’t have life.

To me state management and aria style accessibility, keyboard events, are the things that are easiest to get wrong and where a library makes the most sense. Things like ESC closes a dialog, activating a popover automatically deactivates the current one, and of course taking care of teardown of event handlers..

Traditionally, UI component libraries have come with too much batteries included, like styles that are always inconsistent. Any customization is either cowboy (—-popover—inner-border-color) or unsupported because of fixed markup (eg title can only be plaintext, can’t use flex layouts, etc). I ended up hating them with a passion, because they lure you in with candy but bite you with treats afterwards.

"Boneless" and "headless" both evoke chicken; a headless chicken equals a dead chicken... So it can't very well be anything but lifeless.