Can specialization lead to unemployment?

This thing had been bothering me for a while and when I spoke with one of my friends who works in the silicon valley, he totally agreed with me that sometimes (and I can say more than that) specialization can and does lead you to unemployment. From my personal experience, it has happened to me since I have been unemployed two times and every time I wanted to change what I was doing before, I was rebuffed and told that since I have specialization in a particular field, I would only get a job or offers for a job in that field only and if I want to start something else then good luck to me. And also if you see in the employment ads, the companies do not even grace you with an interview if you don’t have a specialized skill set. So this so called specialization can lead you to unemployment if you happened to get laid off in the first place. Specialization has become a double edged weapon because with it you can land a high coveted job and also can land on the unemployment line if you cannot find one. And this is how the employment world has come to view the employees as. You cannot function in a job without being specialized in some field and you feel handicapped if you don’t have that specialization. That is why you will consistently see high levels of unemployment because there can only be so many jobs in one specialized field and if the supply of specialization in one field exceeds the demand then good luck getting a job.