You don't necessarily stream continuous data at full speed through USB 2.0. For example it has 2x I2S, so with the right firmware and audio class 2 drivers, it could be a 24 bit 192KHz USB-I2S bridge. Which is only 9mbit/s but it doesn't fit to USB 1.1 speeds.
It looks like a very capable chip. Does this RISC-V4F have execute in place capabilities for external flash?
Good point. There is a huge gap between 12Mbit and 480Mbit, and 100Mbit and 1000Mbit. tens of Mbit with flow control (USB, TCP) is plenty of data to manage for a MCU, but can be an useful application.
Especially on USB aspects you don't have to worry too much about "Denial Of Service" attacks, which on networks (even LAN) can be a problem.
I must correct my previous comment as well. The 2.64 Coremark/MHz shown in the link is just a random sample. Looking at the Makefile, there aren't that many optimization flags added to make it run just that bit faster (with an unrealistically large binary size). It may account for 10-20% extra gain, but compared to the Coremark scores databases with optimized builds would bring it a lot closer to a Cortex-m4, making it a decent mid-range MCU.
Yeah, a few thoughts:
- Not to sound offensive at all - sorry if it does sound so - but, I think many chinese companies have a "loose interaction" with intellectual property in general (in particular that of others), and fully respecting open-source/free software licenses is not necessarily one of their main concerns.
- There are companies that make their modified source fully and easily available, but it only very moderately helps anyone building/maintaining their own version. Microchip comes to mind.
- And yes, as newbrain just said, I guess the huge majority of users do not care anyway.
I think you first thought is a genuine truth

I've been able to speak to some Chinese people/students over the years, and the impression I've got is that "innovation" has a different meaning than here in the west. Just look at the number of STM32F103 clones out there: afaik you almost need more than 2 hands to count them. There is no real incentive to make something unique, if you can also boost the economy by making it less dependent on the west. (Now these people may be biased since they are actively chasing opportunities to go abroad, and stay abroad and away from China if possible.)
Imagine all the time spent reverse engineering to make a functional equivalent clone at a RTL level, instead of making a HAL API compatible chip, or something unique that's simple to use and program. You can also see it very clearly in this device: the manual is shared with a STM clone, with RTL and naming conventions also straight copy-paste. It wins big in familiarity on that front.
Would I care? Yes, but no, but.. AFAIK STMicro isn't doing too bad, by having sold everything they got, I can see why people would go/need to use some "clone" or IP infringing product. However, what if STMicro would scale down their MCU branch, or go out of business, because nobody buys their stuff anymore? Then I would have a big problem with it. I wouldn't be amazed if they are pushing hard to have transports of clone chips into EU/US banned/actively enforced, including reels of bare chips but also finished devices. After all, you can't bring in a counterfeit Rolex from your holiday destination, so why would you be able to buy a counterfeit or IP infringing MCU.
On the other hand, we also openly discuss how to feature unlock a scope/etc. because we're of the opinion we already paid for the hardware, and it's MY hardware, that has the capability to do feature X. So what gives. As a hobbyist, if I can get my hands on silicon that can run code and toggle it's pins, then that's already alot to be happy about.
Concerning MCP XC compilers: it's sad to see the state of it. I honestly think that if MCP had better tools they would have been a lot more popular. However, if you compare it to Espressif, is that situation really that much different? I mean, do you also compile your ESP8266 or ESP32 binaries with WiFi support WITHOUT using ESP-IDF and just using mainline GCC?
My own answer to that question is yes: their situation is different. The low-hanging fruit answer is they don't charge for a "pro" compiler. But I think the more elaborate answer is that they have made tools that don't outright suck from an users perspective. It doesn't take 30sec to upload a 16K binary to a PIC32 chip. It doesn't loose USB connection to a PICKIT half of the time. The debugger firmware doesn't have a mind of it's own, etc.
Certainly it is possible to dive deeper into the tools and get something to work. For example, just the other day I was able to get code for PIC32s compiled and debugging code happily on MIPS GCC 11.3, GDB and OpenOCD over JTAG. It is
possible, but I feel a bit ashamed it had costed me almost a full week of tinkering to get the settings in dialed right to get something that seems to work.. but can't be certain it's 100% crash free. But from my point currently, XC32 is not much more than mainline GCC, some crt0, header files and libraries, and finally commandline adjustments so you can type -mmcu=PIC32MX795F512H instead of -march=m4k -mtune=4kem, etc.