trpc relies still on strings: No proper refactoring (ie F2 in VS Code) which makes refactoring as slow and error-prone as with REST and GraphQL. Should change with v10 but its API hasn't been finalized yet and ETA is far in 2023 if at all. Also overall API design has missed opportunities.
Telefunc should support zod, why shouldn't it? Just pass them as native zod types and all good. You could also convert them before with z.infer but you don't need to.
> It seems like this library has its own bespoke syntax for types
Only for stacks which don't transpile server-side code. You can use normal TS types with something like Next, Nuxt, Svelte, Vite, etc. So, these bespoke types aren't relevant for the majority.