Apple will introduce these key Messages app upgrades very soon, here's what they are - 9to5Mac

Apple is set to introduce significant upgrades to its Messages app, including support for end-to-end encryption with RCS, enhanced messaging features like reactions, editing, deleting, and inline replies, and the ability for some carriers to enable encrypted RCS messaging by default. These upgrades are expected to be part of the upcoming iOS 26.4 release.