Can't connect to wifi Raspberry Pi 3A+

[TheOldPresbyope]

So it's actually working the way it's supposed to. I thought that wasn't the case.

For reference, the ever helpful Arch LInux wiki wpa_supplicant page gives exactly the same instructions for connections to mixed WPA2-PSK/WPA3-SAE access points so it's not just a Pi thing.

Regards,
Kent

Indeed, and even a different way for pure WPA3-SAE access points, where it asks for clear text password 
I'm starting to believe that this is a problem with devices relying on wpa_supplicant, maybe the ones that didn't require any extra configuration were using a different tool to manage wi-fi, after all when I checked in Kerberos.io that file was almost empty. 
Or maybe previous firmware versions were able to handle it without explicit configuration.
Going to try again in the weekend and get to the bottom of this...

But to me this seems like a bug in wpa_supplicant more than "working the way it's supposed to" since all the other devices and SOs are smart enough to detect what encryption to use...

At this point, I'm not yet convinced it is a bug in wpa_supplicant per se but in the way it's built/and or configured. It's ubiquitous in Linux-based systems including Android and I see that recent Android releases explicitly claim they support the various WPA3 modes including this mixed WPA2/WPA3 mode (aka transition mode in some of the things read).

In any case, you're the man of the hour for bringing up the issue and doing the digging. Without a suitable WiFi testbed, either a commercial router or a openwrt install, I'm not in a position to do what you can do.
F
Sadly, the documentation of the WiFi subsystem of Linux is as obscurely documented as the ALSA subsystem. If you like waltzing through alphabet soup, have a look at the wpa_supplicant.conf docs: /usr/share/doc/wpa_supplicant/examples/wpa_supplicant.conf

Regards,
Kent