Hey Fred,The feature you're all searching for is called "focus selector lock" It's that manual "L" ring around the multi-selector button on all the DSLRs... The Z cameras eliminated the manual "L" ring and assigned the function to a menu option...
Custom Setting Menu
f Controls
f2 Custom controls
Sub-selector (joystick) center
Select center focus point
That would be the logical thing to do... I don't have a Z camera to play with to try to figure out which might the best process...I'm stunned, after decades of Nikon putting a Focus Selector Lock on their cameras, that they decided to do away with that feature... Although, as you mention (accidentally locking the ring) has been the basis for a brazillion posts on various camera/Nikon forums over the decades too...I think I am going to assign the center button to a pre-assigned focus point again.
Yeah, the amount of time it has taken me to figure out I bumped that ring has gotten a lot shorter over the years.That would be the logical thing to do... I don't have a Z camera to play with to try to figure out which might the best process...I'm stunned, after decades of Nikon putting a Focus Selector Lock on their cameras, that they decided to do away with that feature... Although, as you mention (accidentally locking the ring) has been the basis for a brazillion posts on various camera/Nikon forums over the decades too...