Just a quick public service announcement, for the pro/advanced user Mac user community on MacRumors...
It looks very likely that you can use the previous generation Thunderbolt 1/2 optical cables (5.5/10/30/60 metre lengths) to connect over distances longer than 2 metres!
And most importantly, it looks like the older TB1/2 optical cable connection can meet the best speed your external storage device can offer, just as fast as using the standard copper Tbolt 3 <2m cables!
The problem to be solved is that, at the moment, there simply aren't any optical cable solutions for Thunderbolt 3 (with the new USB-C ports), unlike the previous Thunderbolt 1 & 2 generations (using Mini DisplayPort). So users who want to keep TB3 devices away from their desks/work stations are not currently served by a native cable.
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However, in my basic testing...
I have a couple of the LG 5K displays that connect via TB3 to the host Mac. The other day I tried to connect one of them to my 2016 15" MBPtb via a Corning TB1/2 10m optical cable I had available.
This was achieved by using Apple TB1/2<>TB3 adapters on each end of the Corning optical cable.
In my testing, it worked flawlessly, allowing connection to not just the display, but also the basic peripherals I had connected to the vanilla 5Gb/s USB-C ports on the back. The only thing it didn't do was power the MBP, as optical cables obviously don't carry power, unlike their shorter copper counterparts which do.
AFAICT, this means that if you have fast (self-powered) external TB3 storage devices, you should be able to run them at a distance longer than the 2m offered by copper TB3 cables. So you don't have to put-up with the often loud noise such mass storage devices make – a top bugbear for most users.
I'm not sure if anyone happens to have had any real-life Tbolt 3 external storage test experience with this; I don't own any fast Tbolt 3 external storage, RAID or otherwise, to test myself unfortunately. So please, if anyone can confirm if they've had any speed differences between a copper 40Gb/s Tbolt 3 cable versus the optical connection above, please do let the community know.
PS. If you want to buy an optical Thunderbolt 1/2 cable, you'll have to find them from third party stores. Apple used to sell the Corning branded ones in their online stores, but currently don't. :-/
