Okay. So, tell me what you couldn't do on iOS that made it closed? I'm really just curious, because this is the argument that everyone loves to use, but never really has a reason as to why it made them leave.
Are you really serious about this question of yours or just trying to provoke another debate where the arguments of others fall under the subjective category of "already known, what's next"?
Try to organize your files in iOS with a file manager (all types!), copy, paste, move, delete etc. like you can do with Total Commander in Android.
Try to connect a USB stick to iOS device and move freely any file to and from it.
Try to download legal files (documents, trailers etc.) from a Torrent sites.
Try to send a file with Bluetooth.
Try to use an SD Card with iPhone.
Try to customize your phone (themes, special icons or even firmware, widgets, apps outside AppStore etc.)
Try to visit sites with Flash.
Try to open multiple apps at once (real multitasking).
Try to charge your iPhone with any micro USB cable.
Try to change your battery.
Just to name a few. Nobody is saying that Android devices are better. They are not. They just give you the feel of freedom, to do what you want with your phone. I used to be an iPhone user from the start, but I switched.
When time came to buy a Tablet it was evident that the iPad was out of question - amongst others - because of the above mentioned.
I am still an Apple fan and will remain so, but I acknowledge and see the limits of iOS, i.e. I won't trade freedom for control.
This post is not about starting an evergreen debate. I answered a question why "everyone loves to use this argument".