Z fc vs. Z 50 (functional differences)

The difference in ergonomics and look between Z fc and Z 50 have been discussed. I am wondering about differences in functionalities.

I was surprised that Z 50, unlike Z fc, does not have a choice of AF-S priority, which is always set to the focus priority. That means that in AF-S focus and recompose are often impossible as the camera locks the shutter if the subject under the focusing square is not perfectly in focus (single-point AF). Since Nikon Z cameras do not have visual focus confirmation in AF-C mode, I prefer using AF-S mode.

Z fc is essentially a Z 50 II (added features). Are there any relevant differences in functionality?

You can also add Z30 because of the newest software and updated features.

<rant begin> It's a still camera, without an EVF (sure) like most of the phones, and it does video as well like them.
I suppose everybody would feel stupid requiring an EVF on a phone, while he sticks to asking one on a camera body. <end of rant>

It's better understood why Z50 will never reach it's cousins' capabilities if you think of it in terms of CPU:

Z50 it's an old hardware derived from 4-year-old project using what was available at the time ...
... and surely not the state of the art nor the top performance for CPU and RAM.
Nikon learned that the hard way, and amended the project with the Z30 ...
...but I don't think there will be a Z50II

Apart from lighter weight and smaller size, is there any advantage of Z 30 over Z fc (still photography only)?

My Z50 doesn't lock the shutter when in AF-S - I'm free to focus and recompose in single point AF. Quickly pressing the shutter without letting the camera focus will also release the shutter.

The Z50 (and other Z cams) also has a better alternative to focus and recompose with subject tracking - point at your subject, start tracking (default subject position is centre of frame), recompose, and then focus. That way there's no need to worry about whether your lens has the ideal field curvature centred on a point a few inches behind your camera - you'll always keep the subject in focus.

The major missing features on the Z50 vs more modern Z DX are USB-C (nice to only need one charger, and you can run the camera off it), 1/3rd grid on the rear screen/viewfinder (1/4 only), and focus stacking.

The Z50 uses the same processor as all other Z cams (except for the Z9 and iis, sort of). Other than the USB port, some buttons, and EVF, the hardware is identical to the Z30

I had shutter lockups while shooting AF-S, but later I did not have shutter lockups with AF-S. I had similar strange behavior with Z 7 when set to Focus Priority. My complaint is that Z 50 is missing an option to set the priority for AF-S, which I always set to Release Priority.

Thank you for the suggestions. They are a workable solution to my problem. I will experiment with whether to change my workflow or switch to AF-C by default.

I own only the Z30 so I cannot make a real comparison.
While I investigated before buying I discovered several, but didn't note down them sorry.

Probably we are speaking about different HDW items.

I read a tech note from Nikon around 3 months ago middle Jan - and it's hard to remember where.
They stated they incremented computational power on the Zfc and did another update using better RAM memories in Z30.

What I'm sure of: the Z30 has the greater cache availability of the three.

What is a cache in a camera? According to Thom Hogan (source Nikon), all Z fc and Z 30 cameras have a buffer of 36 frames for raw.

You are correct, only Tom Hogan mentions that on the web.
Nikon itself doesn't mention it, not even in the manuals

Cache in a Computer, and E-Camera are also Computers,
is the space available for the CPU to park information and instructions while processing them.

Not specific to "how many" frames for a camera or "pages to print" for a PC.

Looking for buffer I came across this info.. for all three cameras - no idea though if they can be useful to you.