And yet, after 30 years of effort from various different, talented people and teams, with historical knowledge of eg, StrongTalk, and Self, and Common Lisp, and Java, and JavaScript, we've yet to see any major leaps in Python performance.

So, in my opinion, it's clearly not as simple as just taking all of that existing knowledge and a good team and just doing it, or one of the many efforts to do so would almost certainly have succeeded by now.