I love the simplicity of StencilJS. Not sure why it's adoption is so low but those guys have put a lot of work. Much better than what Google is doing with Lit Element.
There's also no types for web components. So, you can't statically analyze your code and know you are indeed passing in the correct property types.
There are wrappers for Stencil components for React/Angular/Vue, so you can ensure typings, but it goes to show the developer experience is far superior at the framework level.