v8 is remarkable but what is described in those links is primarily a JIT with a cache tacked on. A pipeline optimized for static compilation would make different tradeoffs.
Indeed, only so much can be done to improve v8 in this regard.
Tracing and other dynamic analysis can do a lot to improve the quality of generated code -- it's effectively a realtime PGO. On the other hand, there's a substantial activation energy in the form of the initial lex, parse, AST generation/manipulation, interpretation and dynamic analysis, re-optimization, etc. that can all be handled ahead of time, albeit with less information to optimize.