Sure it does. Right side button, hold it and it triggers siri. Single click locks unlocks the phone. This is identical to how the unlock/Bixby button works on Samsung.
That’s optional, and opt-in -- it asks you during phone setup whether to enable Siri.
It does try to nudge you into enabling it, but if someone kept pressing that button and invoking Siri accidentally, they could open Settings and search for “siri” to disable it, which I think is reasonably discoverable.
On my S10, there is a seperate Bixby button on the left side, so it's not shared with the unlock button. The best thing about the Bixby button is that I can freely remap it with third party applications, meaning I have a dedicated, customizable, physical button, something all phones should have.
Sure it does. Right side button, hold it and it triggers siri. Single click locks unlocks the phone. This is identical to how the unlock/Bixby button works on Samsung.