What “cloud data”? Most apps that are available for iOS are also available for Android and are subscription based these days.
Copying data from iCloud Drive to another cloud provider like Google Drive can be done in the Files App.
Music you bought has been DRM free since 2009.
Apple works with MoviesAnyWhere. Four or five of the major studios participate too. Meaning any movie you buy from one of the participating studios can be synced to Amazon Movies, Google Play Movies (or whatever it’s called these days), Vudu etc.
Photos can be synced to Google Photos, Dropbox, OneDrive.
Bookmarks can be synced between Chrome and Firefox and Safari if you have a Windows PC using Apple’s extension for those browsers.
Each of those steps is distinct and requires it's own process.
Those in the know can switch.
Those who just have a phone are looking at a hard to judge effort that might take months of "where was that?"
Don't just discount the literal day it would take a tech person to switch their primary phone as meaningless. Nor should you discount how many people don't even know it is meaningfully possible.
I am pretty sure I knew people back in the early days who wanted to switch so they just lost everything from before.
Is it really difficult to say “I have Spotify/Apple Music/Office 365, random other subscription. Let me download the same app on an Android phone”?
People have been using copy and paste to copy files from one drive to another since Windows 95. It works the same way with the Files app. You download the other storage provider’s app and they show up in the files app. Heck you can literally attach a USB drive to your iOS device and it shows up in the Files app like it would hold computer.
Syncing photos is as simple as downloading Google photos.
You can literally Google all of this stuff.
As far as it taking “a day”. It takes me about as long to set up a new Windows PC.
And it’s not worth a day of your life to jump over Apple’s “walled garden” where there is a big ass door that you have to push on a little bit?
