Apple's going to have to figure out a new way to make money. That's not snark, just a fact. They give away the development tools, give away software upgrades, and monetize all that work via the apps themselves. Expect XCode to have a price tag if this passes.
There are legitimate security issues with other app stores, and I really wonder if the EU realizes that the first thing facebook and other data-privacy invading companies do will be to leave the apple app store and their restrictions and launch their own 'ad and data selling friendly' store. Apple loses the ability to be the privacy gatekeeper. Left hand meet right hand.
On iMessage, sorry. There are plenty of competing systems, and forcing apple to open theirs up (aka stealing their IP) is bogus. If google had picked a strategy and stayed with it, they'd have a similar app. Just because they blew it, doesn't mean apple should have to give them a second chance.