Google seems much too sure of itself making this change. I hope their arrogance pays off just the same as Microsoft's did with IE.
I think it's part of a much bigger trend in tech in general but also in Google: Removing user control. When you look at the "security" things they are doing, many of them have a common philosophy underpinning them that the user (aka device owner) is a security threat and must be protected against. Web integrity, Manifest v3, various DoH/DoT, bootloader locking, device integrity which conveniently makes root difficult/impossible, and more.
To all the engineers working on this stuff, I hope you're happy that your work is essentially destroying the world that you and I grew up in. The next generation won't have the wonderful and fertile computing environment that we enjoyed, and it's (partly) your fault.
That said, I don't like that the choice is being taken away. If you do want to tinker at that level with the technology you own, you should be given the choice. By all means make it not obvious how to get there - like, have people reboot their computers while playing Twister on their keyboards with interesting key combos, but give them the option.