Your argument is "well maybe they won't be secure tomorrow and you're invested". Ok, but they are secure now and that's more than pretty much other major tech company. Yeah there's lock in with Apple, you don't think there is with Google too? Apple is worst I'll grant you but no one's innocent. Hell Microsoft had to pay 10s of billions for that kinda shit on the 90s. And let's not even get started on Google or IOT where they stop running the service and you're just SOL.

Apple give me privacy. Find a company that doesn't and doesn't have lock in and I'd switch in a heart beat but based on simple economics I doubt that's gonna happen any time soon