I'm not an official anything - but the sample engine is not tied to USB. USB is not a memory bus that participates in the sample playback. Even if it was fast enough - the architecture isn't there to make use of it. USB is a mechanism to stage audio files and get them loaded into Monrage/MODX memory space where sample playback does occur. It is here in internal memory where sample playback is allowed.

If Yamaha is looking into sample streaming or not is a question not likely to get answered. At least another non-Korg keyboard manufacturer has claimed to be doing feasibility studies into adding stream-from-storage features. I don't think we will be shown any cards even if there was a similar feasibility study conducted at Yamaha.

Just wondering, would the current USB ports be fast enough to load samples directly from USB stick?

So where does this question come from?
I am moderator of a Montage facebook group, where this question keeps arising.
Personally, i am pretty sure the USB port is not fast enough for this.
Having this question answered by product specialist would be helpfull to back up my answer.

I think the current USB is fast enough to allow for pretty much any data be loaded real time, except samples.

Welcome to YamahaSynth!
The question is not really clear. Here’s why...

You can currently “load samples directly from USB stick”.
“Load” being a technical term that means transferring, in this case, a .wav or aiff audio file into the internal memory of the MONTAGE. That you can do now. You can LOAD an audio file directly to a MONTAGE AWM2 Normal Part or Drum Kit.

Within Part Edit, on the individual Element screen, you will find the “New Waveform” box
Tap this to be taken directly to the Load Audio File screen. If in a Drum Kit, each Key will have “New Waveform” option.

Waveforms that meet the criteria can be loaded directly into the internal memory — where they are placed as a USER Waveform.
User Waveforms can be Saved in .X7U User Files or can be saved to a Library File .X7L which then allows you to install them into ROM Library.

Some how “load” may not be the term they wanted to use...

If the question is about using a (cheap) device like a USB stick in place of the internal FLASH memory - that is, could a USB stick be used to hold additional samples that could somehow be streamed in real-time? NO. It is not robust enough to do this job.

The type of memory used to hold audio in your MONTAGE is able to deliver 128 Notes of stereo AWM2 and 128 Notes of FM-X within nanoseconds of your request (request is sent by touching the keys).... the inexpensive type of storage found on a USB stick can choke on delivering much beyond a single stereo channel of audio within several hundred milliseconds of the request. It simply does not have the bandwidth to handle streaming that many stereo channels simultaneously (it ain’t even close).

So streaming audio from a USB stick for real-time playing of the synthesizer = NO,
__ by the way, the MONTAGE does stream audio... you can insert a USB drive into the “To Device” port and record 74 minutes of Stereo audio directly to the USB stick. You can, of course, stream the playback from the USB stick. It is, of course, one stereo channel. That’s 2 channels, a Left and a Right — the latency on that type of memory device trying to deliver 128 stereo channels of audio would be ludicrous ...

Frankly, it is a standard newbie question... because they can buy GBs of memory on USB sticks for dirt cheap, they think all memory works the same. Obviously, what they are unaware of is there are many different types of memory. If you’re storing documents (legal stuff, ledgers, pictures) timing of moving data around is not critical - you just need to access it. Music making is a demanding thing (Miss a mere 64th note, watch a musician scream).

When you stream audio from a usb stick it could be 200-300 MSec between you pressing play and the music starting to stream... hardly noticeable ... EXCEPT to musicians... if that is you attempting to play an Fminor7b5 - (that’s a request) and the sound is returned by your storage device 250ms behind you pressing the keys, you can’t play like that. You want an immediate response to your request.

The memory in the internal MONTAGE (Presets) and for the installed Libraries, is not only a different kind of memory, it has a different purpose, and it is quite a bit more expensive (lol). You can ask them if they ever bought memory for their computer. When selecting options note the prices of the memory... the speed with which the memory can be accessed is CRITICAL particularly so for musical instrument applications... and it comes with a price. Nanoseconds - is really, really fast

Thanks for moderating a Facebook group that helps MONTAGE users and thanks for getting the information back to folks. That’s awesome!!
Please reassure them, that at Yamaha R&D, virtually no stone goes unturned when a product like MONTAGE and MODX are planned. If it were possible - why on earth wouldn’t we be doing it? lol.

Extra Credit:
Makes for excellent reading... link = Sand Software and Sound — Montage Hardware Platform