If the reason he's using a horribly unfriendly and difficult to debug API is because it's cross-platform and the more developer-friendly replacement is Linux only, then the fact that the API is so hostile certainly isn't proof - as bcantrill was claiming - that Linux is somehow going out of its way to be hostile to developers compared to competing OSes.
PF_KEYv2's difficult interface definitely isn't a Linux issue. But PF_KEYv2's limited error reporting means that understanding what's going wrong requires kernel debugging. The difficulty of kernel debugging is a Linux issue. ("I do not condone single-stepping through code to find the bug.")
> I want my application to work on OS X and Linux, so I’m targeting PF_KEYv2 instead of OS-specific APIs.