“The Linux vulnerability was fixed in 2020 (CVE-2020-0556), but the fix was left disabled by default.”
A Linux laptop with a normal Bluetooth adapter can pose as a keyboard and pair without the user confirming anything. Then it types whatever it wants. Android is vulnerable back to 4.2.2 from 2012, and Apple’s devices fall even in Lockdown Mode. Linux had a fix for three years and only ChromeOS turned it on. Ubuntu, Debian, Fedora and Arch announced the patch and shipped it switched off.