I’m talking mostly about musl, but Void with glibc still requires more work than a “just works” distro. As such, I didn’t see a point in trying Void with glibc, because the biggest benefit I saw to switching was for musl. It’s great for some, but not for me, just as I wouldn’t use Gentoo. There were a lot of things that didn’t run, I don’t have a full list. I know for a fact that Steam (or any Steam games) wouldn’t run, I’m fairly confident that the OnlyOffice suite wouldn’t work, I believe that EasyEffects wouldn’t run which was a big problem, since I use that for system wide equalization, and for my microphone filters. I probably could have figured out how to set everything up with bare PipeWire, but it’s basically the same story for everything: it just requires way more work. My VPN (Mullvad) isn’t compiled for musl, nor was the Nextcloud client, and many things I use every day. Those are just the things I remember having issues with off the top of my head, and it may not have only been musl that was the problem, but it’s very likely it was.
It runs JavaCard OS, which is developed by Oracle and not open source. Even though it also runs JavaCard OS, I’d recommend the flexSecure JavaCard from Dangerous Things (for the same price as the Apex Flex), because all of its applets are open source: https://dangerousthings.com/product/flexsecure/. It isn’t quite as “seamless”, because it doesn’t have the closed-source app store available for it that the Apex Flex does, but it instead uses open-source applets that you can load onto it. Regardless, either option will run a closed-source OS, but as far as secure verification goes (by using challenge-response instead of static keys which could be read and copied like old RFID tags), JavaCard is currently the best option. And as far as implantable chips go, the flexSecure JavaCard and the Apex Flex are the 2 best chips on the market to my knowledge.
The silver lining is that there are plenty of open source applets you can run on JavaCards (like the flexSecure ones written by Dangerous Things)