alt Hacker Newstypedefs are indeed automatically exported but that doesn't mean collisions can happen. You would still have to explicitly import a type
Regardless, I hardly consider that a "missing basic capability"
I don't know what you mean about types for classes being "poor". Types for classes work exactly the same way
You cannot replicate `import type { x } from './foo'` without also re-exporting that import - which causes collisions.
The alternative is to do an inline `const foo = /** @type {import('./foo').x} */ ({})` however this gets messy, repetitive and it's difficult to use algebraic types (e.g. `Event & { detail: string }`)