There's not a snow-balls chance in hell I would have these be wireless, or a proprietary standard:
1) Latency. Anything over 2ms is not acceptable for live music. That's the difference between a band sounding "in-time" to "needs practice"
2) We use various tablets, phones to control the mix to our ears, and sometimes in between sets, listen and review music.
3) Removing the 3.5mm pretty much means Apple is exiting professional audio because it's now incompatible with 100% of everything.
4) There is no way in hell my $300 pair of custom-molded IEMs bound to a standard that Apple is going to change in 3 years. Not only would I have to replace my IEMs, but any equipment that's not Apple would have to be updated to match. Not going to happen.