What does it even mean?

They are made much better. Sturdy af.

But koss have cool sound that I was into in my early teens.

As it was discussed, monitoring means being able to hear yourself when recording the performance.

Monitoring headphones should not be flat at all. Ones of the best monitoring headphones are 770's and m50x's.

Their spikes are intentional to make the singer record the vocals so that sibilants occur less and for better upper detail retrieval. Narrow soundstage also helps with that.

I don't know if it was designed with that in mind, but we use them for that specific reason as well as many other recording engineers.

And yes, no one is seriously mixing with those.

This is not monitoring.

It would be monitoring if you were to play electronic drums through those earbuds.

Monitoring is being able to hear what the recording equipment is "hearing".

Wireless pack isn't bluetooth. It's radio.

Attaching a bluetooth transmitter to a radio receiver doesn't seem practical for me considering the latency and quality issues

This is the wrong tool for the wrong job.

As my grandpa said, you can hit the nail with a microscope. But if you can, it doesn't mean you should.

There's more to that than just hearing your voice.

I'm talking about listening to stuff that's being recorded or performed.

For example, you are tracking vocals and you are too forward and the proximity effect is giving you too much lower frequencies. You won't hear that with transparency mode.

Or you are tracking the guitar and need it to have an instant response (up to 10 ms latency is fine). You won't be able to play to the click if the latency is too big.

Hope you get my point.

For me, the last border is them being wired.

If the earbuds are wired and are of higher quality, they can be called iem in my book.

As long as they're wireless, they're tws buds.

Monitoring means being able to hear yourself through the recording/live performance equipment. That's not the case with wireless headphones of any sort as of now.

The first issue is latency, especially on instruments

Then there's quality.

And finally, you can't connect bluetooth headphones to the interface/radio system with no additional gear which can be an issue

They're IE, but not M.