One major thing that has held back Web Components, IMO, is that the standard never provided a JSX equivalent: a convenient declarative, condensed way to express your component's structure along with event handlers. So if you choose to build web components, unless you want to have a terrible developer experience, you're still going to reach for a library anyways, like Lit (the successor to Polymer). Only unlike using popular libraries like React/Vue/Angular, the ecosystem, community and resources at your disposal will be much smaller.