Same with Android - from 2008 to ~2018 I was rooting and putting custom ROMs on my phone before I'd even got it home. These days I rarely bother because the functionality that I required is finally provided out-of-the-box.
It's no longer my phone If I can't decide what gets installed and what shouldn't
It is possible to reject the update. Just disable automatic updates of the Google App in the Play Store. You could even return to Google Assistant by reverting Google App to an older version.
What is really needed is being able to choose what updates to install, and more generally, being able to get rid of all the crapware that uploads everything you do on your device to your corporate overlords. Not just particular "apps", but the operating system itself.
The fact that most people in 2025 simply accept carrying around 24/7 a device with GPS, microphone, camera and wireless network connection, which they cannot control or even know what it does at all, is dystopian.
Imagine if this was the norm with PCs back in the 1990s. Linux would never have existed, since there would have been no way to replace the pre-installed Microsoft OS with something else.