And, on a comparable processor, properly developed apps are not any slower than on iOS. .
It's not "properly developed" -- it's properly tailored to a Java platform.
Whether an app can run on Java well depends on what it does.
It depends on the type of app. Any app that does serious number crunching will suffer running as Dalvik bytecode.
Programmers have limited time -- especially hobbyists. Not everyone can get around to doing a properly tailored Java app whereas iOS offers an abundance of processing power and doesn't require extra modifications.