...
Intrinsic support for OpenRoaming exists on later (read, newer) devices and versions of Android. For example, recent Google Pixel devices (Pixel 5 and later) show "OpenRoaming" as a network when a HS2.0 hotspot is detected. You then have the choice to enable roaming to this network by choosing to use your Google account associated with your Android phone. Apps like 'Cisco Openroaming' also enable an account on the same network. CAT profiles installed with geteduroam will show "<realm name> via Passpoint" instead but do not associate with the "OpenRoaming" SSID. On some Samsung devices, you may see "OpenRoaming available using Samsung Account" instead, which will function in a similar fashion as the Google Pixel.
Linux
TBD.
ChromeOS
Any recent version of wpa_supplicant supports Passpoint, provided it has been built with the CONFIG_INTERWORKING=y and CONFIG_HS20=y flags. Check your Linux distribution's build source configurations for confirmation. Instead of using a network {} block (as you would with a standard 802.1x network), you use the credential {} block.
To enable Passpoint roaming, set interworking=1 and hs20=1 in your wpa_supplicant.conf, and provide the credential block to use.
More information is available at https://github.com/xradvanyip/hostapd-openwrt/blob/master/wpa_supplicant/README-HS20
ChromeOS
Recent versions of ChromeOS should also support Passpoint. Google is active in the Passpoint community. You should be able to use the geteduroam app for Android on ChromeOS to configure your ChromeOS device for Passpoint. TBD.
Infrastructure
OpenRoaming
...