Google finished adding full E2E encryption a few months ago. It's actually more secure than iMessage now since your RCS messages aren't stored on the cloud like iMessages. I'm guessing this is also one other reason Apple is adopting RCS.
https://www.theverge.com/2023/8/8/23824800/google-messages-rcs-end-to-end-encryption-default-group
Google finished adding full E2E encryption a few months ago. It's actually more secure than iMessage now since your RCS messages aren't stored on the cloud like iMessages. I'm guessing this is also one other reason Apple is adopting RCS.
https://www.theverge.com/2023/8/8/23824800/google-messages-rcs-end-to-end-encryption-default-group