That is what kept me out of Linux when I was a teenager, but it was MODEM drivers at that time. Lack of driver support for an operating system is not a technical problem, it is a social problem.
Essentially, it doesn't matter what mechanism generates the signals except when it came down to me wanting to play with Linux twenty years ago and a company decided to release a product that was only compatible with a single operating system. My desire to play with Linux did not happen to be worth as much as it would have cost to do so at the time, so I waited.
It does. The soft modens were partly a lockin technique to decrease odds you'd be able to use something like Linux without buying new hardware. The strategy apparently worked. It's why I push for standards-compliant hardware that requires no funny business to use in new ways.