We’re not sure what keyboard you purchased, you don’t really say. But since you posted in the Motif XF Forum, we’ll assume you purchased a used Motif XF - the product came out in 2010 and was discontinued at the beginning of 2016. So it could not have been NEW (new to you, probably).

The Motif XF has 16 audio bus outputs via FireWire and it became a 16-bus Audio Interface for your computer (it did not do Audio to USB stick. Back in 2010 we were just introducing that in our Stage Pianos, CP1 and CP5). The Motif XF was designed to be the center of a pro home multi-track studio. Back in 2010 USB could only handle stereo recording and playback; the Motif XF, therefore, used FireWire so that 16 audio buses were available.

But you can record Stereo (2) Tracks of audio directly out from the MOTIF XF, either via wireless USB, or via Ethernet with the proper connections and applications.

Link — CLOUD AUDIO RECORDER — this app may still be available where you live (it is marked US, here, so I can’t say if it is still available in Europe)
Link — Cloud Audio Recorder

Back in 2012 Yamaha released a free App specifically for recording audio from the Motif XF wirelessly to the Cloud Audio Recorder:
Link — Cloud Audio Recorder for Motif XF — This was discontinued when the synth was discontinued in 2016.

If you don’t have an iPhone, iPad and WiFi etc., you can get a handheld recorder (it’s what you would have done back in 2010 when the Motif XF was new). May we suggest that next time you are purchasing a synth, you visit a local music store that carries Yamaha… certainly they would have been able to tell you about the current Yamaha synthesizers MODX/MONTAGE

— when you buy used keyboards, it is really your responsibility to research them — assuming a feature that was not yet implemented to the synthesizer line is like buying a used MiniMoog and wondering where the 128 note polyphony is… it simply wasn’t available at the time the keyboard came out! And you had 11 years to figure this out…

Sergiu-Daniel is somewhat correct. Audio recording on usb was available in 2010 in Tyros 4. Workstation like Motif should also have it. This is my opinion 😉

Your opinion notwithstanding, the Tyros 4 has little to nothing to do with the Motif XF. It did not feature the 16-bus audio Output that was available for the Motif XF (in spite of the fact that the 61 key Tyros 4 was hundreds of $$$ more than than an 88 weighted key Motif XF8). Your opinion is free, (doesn’t make it correct) the features are not. And doesn’t change the fact that in 2010 we did not have a synthesizer with USB Audio. If that is the feature you desired back in 2010, the Tyros 4 was the correct choice — it’s not like you didn’t have a choice.

Back in 2010 when I asked a non-Yamaha music expert what audio interface I should buy they still primarily responded Firewire. Although USB was available - USB 2.0 which is used today in Montage was a decade old by 2010 - the "high end" interfaces were all firewire. The industry wisdom at the time was that Firewire was reliable/stable while USB was unreliable. Most of what happened in the coming years was an effort to improve the drivers for USB not to mention the hand forced by costs of Firewire (licensing, extra parts required, etc).

2010 was a transitional year for Firewire to USB - but Motif XF's design cycle preceded 2010. By the time you cast a product out to sea - it's prohibitively expensive to rip up the entire design and replace it with something else.

Had the design started in 2010, 2011 - perhaps things would be different. However, products are designed within the paradigm of the moment and are subject to what's best at the time. That best practices have changed since then is called progress - not a mistake or lack of precognition.

Around this same time, Apple's licensing fees for Firewire - Apple's removing ports from product lines - and relative expense of implementing Firewire vs. USB placed the nail in the coffin for Firewire. This was not anticipated in the years prior when Motif XF was in its infancy (design-wise).

The trend, with Yamaha, has always been to trail technology. Even today one could argue that USB 3.0 has been available for long enough to be stable including both hardware and driver offerings. Yet the current I/O bus is USB2.0 based.

It's a lot different looking backwards (in time) than it is looking forwards at features.

Even today one could argue that USB 3.0 has been available for long enough to be stable including both hardware and driver offerings. Yet the current I/O bus is USB2.0 based.

RME launched a very high-end interface this year, 2021 (the Fireface UCX 2) and it uses USB 2 because, as one of their tech guys explained, "USB 2.0 is good enough for 70 channels record PLUS 70 channels playback (RME MADIface Pro), the UCX II has only 20 channels per direction."
No need to break compatibility if the features (bandwidth in this case) are not needed.

Latency may be a reason not touched upon in the description about channel capabilities.

The "to device", although not discussed prior, would be a good candidate for USB 3.0 in order to make save/loading faster if the rest of the system can keep up with the USB3 speeds.

However, I'm more generally saying that staying on the trailing edge means the future can intersect in dissatisfying ways. That said, it's probably safer than being too bleeding edge. overall.

Latency may be a reason not touched upon in the description about channel capabilities.

If there's one reason RME interfaces are famous for, it's exceptional latency, which is the case with this model as well.
My point was that being conservative has it's advantages as well. In that example, adopting the latest would bring zero advantages (no better speed, no better latency) and some compatibily disadvantages.
I don't think the saving speed is because of USB 2. There's something else that slows the operation. For example, just getting the name of all performances updated in the John Melas suite is a very (very) slow process as it goes thru each one and dumps the data as MIDI.