Indeed, it's also the case with audio interfaces, no major audio interface company releases Linux drivers.
From my (programmer's) point of view, all I need to know to work with an audio interface is the number of input and output channels and the respective arrays of sample rates and bit depths. In theory, a generic USB driver can handle that. In practice, I observe that my Linux-using colleagues have 99 problems with audio, but none of those is related to plugging in a $1 dongle from AliExpress. (Therefore, I used to think that those audio interfaces ‘just work’, but now I'm curious about what I've been missing all along.)
Why is releasing Linux drivers for an audio interface even a thing?
However, it seems like that explains why we needed Windows drivers, but not why device-specific Linux drivers are a thing? Unless the implication is that manufacturers who needed to make custom drivers anyway didn't bother to make their devices class compliant?
Linux should support all these "class compliant" audio interfaces too, but I can't remember if you need extra software (like JACK?) for this.