Yup that's basically it. If you have some electronic device (like an Android or iPhone), you can go to some sort of "about phone" setting page and poke around for a licenses button that'll show you all the software that your device uses. It's just proper attribution.
I've done reverse engineering and found obvious illegally used GPL code in closed source projects, and they could (theoretically) get in big trouble for not following the license. (I anonymously requested their source based on the terms of the license, but the company threatened to sue for reverse engineering, so it's often not worth it)
That virtualization thing hasn't really been true for quite a while. Android compiles the Java-ish code ahead of time (the .oat file is a playful acronym for "ahead of time") to native code. There's still overhead with exceptions and other java-isms, but that still very much exists in objective-c.
I'd bed that iPhones only seem faster because it's normal to have more powerful and expensive new iPhones. Android has auto-suspended apps in the background for longer than iphone, and it doesn't require any maintenance to keep running smoothly (it doesn't even require "closing" apps from the app drawer).