I'm curious as to whether or not this definition makes sense to other developers? ECMAScript does have a built-in "Object" data type, though I wouldn't say that this is it's "core abstraction". Further, firmly object-oriented languages, such as Java, seem to lack this abstraction. Perhaps I'm missing something in the definition?
(meanwhile, Scheming away in the background ...)
java isn't necessarily more object-oriented than other options. generally, i think when people say "oo", they're really just referring to nominal subtyping; probably due to the language's ubiquity (as well as c++ and c#).
this nominal subtyping gives rise to the hierarchical taxonomies of object-classes that are a quintessential characteristic of java, c# and friends.
There is also the big-"O" Object (sometimes called the "Object object," hah). This is a place to hang useful functions and also serves as the default prototype.