Excellent question: In a theoretical sense the answer would be that we cannot know since it depends on the JavaScript being run. But: In practice I think that is indeed the case. Especially for the more common an object is, the likelier it is that it is used in conjunction with others around it. At the same time, the more important their memory placement becomes.

eg. Say you have a JS programs that has about a 100 DataViews: I'd say it's unlikely these are used in conjunction with others very often, but they're also only a small part of the program, so their placement is mostly whatever.

Now what if that number is a million instead? Now I'm betting they're mostly all created together, used together, and that their placement is critical to the program's performance.

So, I'm betting that making random memory access performance worse while guaranteeing that data created together stays together and improving linear memory performance will be an overall win.

Whether this is true data-oriented design is then in the eye of the beholder: Maybe someone will think I'm wrong, my assumptions are wrong, and I'm thus not doing things in a data-oriented way.