This is what makes me really undecided about switching jobs. I've been working in the same domain for almost 20 years. I think I'm a very competent SWE, but I also think my domain knowledge is what really impress my customers.
If you're happy where you are, stay there. Don't get too high and mighty, learn what you can from the people passing from one domain to another without staying in one spot too long, but don't feel pressured to do what they do as if you are missing out on an essential experience of life.