So, for the build time translation-
Yeah, I would say it's not reliable yet =p
But, it's not that far off. It's not magic- the idea is that we inject the t functions at build time so that they don't need to be in your code. The vscode extension is a good visual for this- for many patterns, it correctly notices what does or doesn't need to be translated.
But, the real problem is that if a process like this goes awry (a strange pattern leads to text being erroneously translated/untranslated) then it is next to impossible for someone to debug.
Glad you think this is cool. We think this is absolutely on the horizon, and we hope to be the first to get people using it... but in the meantime, we don't want to be responsible for issues on prod...