Apple has moved these indicators into their “exclaves” removing any control or influence from the OS / software running.
Source? AFAIK they only have hardware indicators for webcams on cams, and it's not used for microphones.
Different person here, but Apple has tried it multiple times in different ways.
They started in ios14, iOS 17 got new Secure Exclave path that (A18, M4).
Search for “Secure Indicator Light”.
Also searching for “Secure Exclave” will reveal some fun reads.
That’s cool, but on iPhones, there is no indicator LIGHT. Only part of the screen indicates it. And if they can trigger stuff on your phone, maybe a daemon that accidentally covers that part with black also appears, and you wouldn’t notice.
Nope, it interfaces directly with the display driver and overwrites anything from user land or the OS.