Yes, it is normal, especially at the salary that we pay (currently $275K). To take but one domain: at that salary, you are (roughly) at the level of a school superintendent for a school district with thousands of students (like, large town/small city). If you have ever been associated with hiring someone in that kind of position, you will see a VERY time intensive process, with many hours of interviews with many stakeholders. So yes, we have an intensive process -- but we take hiring very seriously, and we believe that it shows in our extraordinary team.
Oh how I wish you guys would hire new grads. I got into kernel dev partly due to zfs and partly due to Redox OS. Well atleast I have worked with Redox now, hopefully someday with you guys too :)