[acadapter]

A small STM32 and libopencm3's USB stack would be a more flexible choice. You could for example set your own name, PID/VID, etc.

With some clever setup of descriptors, you could even have multiple UART serials to one USB connection.

[tssva]

I think the point was to make something in a pinch with what was already available versus making the most flexible choice.

That being said I use, I'm not the author, https://github.com/Noltari/pico-uart-bridge to turn a Raspberry Pi Pico into a USB to dual UART adapter. It appears as a CDC-ACM device so is supported under Linux and Windows without any 3rd party drivers. I replaced my MacBook Pro with a Thinkpad years ago so I have no idea what the situation is on macOS.

[ta988]

Or a $4 RP2040 board.