Yes, the complexity of modern hardware makes it hard to keep up. For example, early wireless cards did a lot of the work in firmware, while modern cards mostly require much more to be done by the driver, including setting up low-level radio registers. There can also be dozens of variants of radio chips used within the same wireless chipset family, which each require different register settings. Additional support is also needed from the OS to configure encryption, negotiate settings with the router etc.
However, I thought Haiku had implemented a compatibility layer to allow easy porting of Linux wireless drivers. But maybe that code is out of date now and hasn't kept pace with changes in the Linux kernel.
