At a guess:

1) Perhaps they don’t want to trigger a different licensing model (on either the music or the lyrics) that applies specifically to karaoke devices and venues. Just a guess, not a music lawyer, but all sorts of unexpected terms apply to music licensing (such as streaming TV services not being able to use music from the original TV broadcast) 2) Perhaps they don’t want to associate with the karaoke “brand” which some users might perceive as kitschy or low-quality (have you ever seen a karaoke video?)

I suspect the second is exactly right. Apple is extremely careful about how their products are perceived as elite and cool and it’s easy to imagine their marketing department thinking the word “karaoke” just evokes an uncool or unsophisticated vibe.

You might be right, but I gotta say that deliberately avoiding the word karaoke feels incredibly insecure and uncool to me if that is the reason.

When I hear karaoke I think 90s looking machine with a tethered microphone, or equally old music videos with ugly subtitles. True or not, it is possible they just want to have full control of the image of their service.

Another thing is that when you sing a foreign song, the karaoke also means to read the foreign subtitles in your own language. It's an extra meaning they might want to avoid, I assume this is not a feature they have.

Perhaps it implies use in a commercial karaoke bar setting which often are dubious for licensing music.

It also might imply perfect vocal removal, which they aren’t guaranteeing.

Potentially trademark issues?

Because karaoke was invented by Hiragashi Karaoke in Japan in the 70s and he has the patent on it.

That's why karaoke is so popular in Japan.

Wikipedia says the patent for karaoke machine is held by a man in the Philippines https://en.wikipedia.org/wiki/Roberto_del_Rosario?wprov=sfti...

It also says that Karaoke in Japan is predated by sing-a-long programs in the US. https://en.wikipedia.org/wiki/Karaoke?wprov=sfti1

Besides that I assume any patent from the 70s is now expired.

Wow I was making shit up but the real invention is actually quite close.

"The world's first karaoke machine, the Juke-8, was built by Japanese inventor and musician Daisuke Inoue in 1971. But it is Filipino inventor Roberto del Rosario who holds the machine's patent. He developed the Karaoke Sing-Along System in 1975."

Why are you posting things you made up?

Welcome to the internet, my friend :)

Probably because Apple doesn't want it advertising to look like:

"Hey we just added a cultural pastime as a feature!"

There are some that could twist this feature into "Apple profiting off of cultural appropriation".

Obvious. Make this look like a more original feature. Redefine the concept on Apple's terms. Have people pay attention to the novelty of it being done automatically, rather than manually in a catalog with lyrics that look like they belong on a CRT screen.