Yet somehow we run SELinux successfully on every Android device. I've never understood the antipathy towards SELinux (which by the way, doesn't operate at syscall granularity).
Most aren't going to do that, though. So, their boxes are still nice targets.
To the end user, they only see your code broken by SELinux, and assume you haven't done your job. On the other hand, SELinux is codifying rules about UNIX that never existed and amount to emotional heuristics about the risk of Internet domain sockets being inherited around the system by the wrong process. The effect isn't to prevent Internet domain sockets being inherited by privileged processes, but breaking all sockets. That's garbage design, hidden behind marketing suggesting because the NSA contributed some code that the problem couldn't possibly be SELinux
Most people first encounter it when it breaks their program in opaque and surprising ways. They then dig in... to find that the solution is non-obvious. So they turn it off and remember it as that thing that breaks stuff.