the fact that a messenging service locks users into an ecosystem.
the fact that to use this an apple device is still used in the background. This means you log in with your apple id on a device that does not belong to you and that can possibly read all of your messages.
I think issue two is a great way to address issue one.
They have made a closed ecosystem to support their lack of innovation and address their declining sales.
But now people could be able to get into this system that otherwise wouldn't and use it without giving apple any information, other than potentially putting actual customers messages and AppleIDs at risk.
Because the android forever people who this is for will not have anything important linked to their AppleID but the people they message likely will or at the very least now their communications are at risk given they go through a third party machine.