alt Hacker NewsJavaScript in 2010 was a totally different beast, standartization-wise. Lots of sharp corners and blank spaces were still there.
So, even if an implementation like MicroQuickJS existed in 2010, it's unlikely that too many people would have chosen JS over Lua, given all the shortcomings that JavaScript had at the time.
While you're not wrong that JS has come a long way in that time, it's not the case that it was an extremely unusual choice at the time - Ryan Dahl chose it for node in 2009.