You call it pigeonhole but a lot of people call it specialization. Some trades require it, others don't. I don't think you can generalize it and call it a problem. It's almost like expecting an expert plumber to wire up your 20 story condo building. Sure you can find a handyman that can do plumbing and electrical, but for your 20 story condo building you are going to call in people that specialize in electrical. And that's okay.
